2 Contents More Homes Through Manufacture A Housing Forum Working Group Report The Housing Forum The Housing Forum is a membership network of organisations and businesses which collaborate to develop and improve the nation’s housing stock. The Housing Forum is the only cross-sector, industry-wide membership network that represents the entire housing supply chain on behalf of the housing industry. We have over 120 member organisations, from both public and private sectors, collaborating to inform, influence and network. The views in this report are the views of The Housing Forum and have been contributed from Working Group discussions and round table forums with senior and leading housing industry figures. www.housingforum.org.uk The Hyde Group The Hyde Group is one of the UK’s leading and award winning providers of housing and a member of The Housing Forum. It operates in London, the South East, the East of England and the East Midlands providing homes with a variety of tenures. The Hyde Group houses 95,000 residents in 49,000 homes. www.hyde-housing.co.uk

47 2015/16 Working Groups Kevin Reed, UK Specification Manager, Graf UK Ltd Geoff Reynolds, Senior Development Manager, Kier Living Robin Roberts, Property Services Director, Worthing Homes Gordon Ronald, Operations Director, Fusion21 Chris Rutter, Business Manager, Fusion21 Manjit Sanghera, TEK and UNIDEK Product Manager, Kingspan Insulation Dennis Seal, Executive Director, Buildoffsite Steve Skuse, Pre-Construction Director, Willmott Dixon Alex Thomas, Key Account Manager, Worcester Bosch Keith Trowers, Senior Business Development Manager, Durkan Jon Wardle, Director, Airey Miller Construction Management Joy Whinnerah, Major Projects Manager, Home Group Richard Wilks, Technical Advisor, Aggregate Industries Chris Wisson, National House Developer Manager, Marshalls Topic Presenters to the Working Group on Offsite Manufacture and Supply Chain Innovation: Rory Bergin, Partner, Sustainable Futures, HTA Design LLP Mark Bradbury, Development Consultant, Climate Energy Homes Graham Clarkson, Director, The Clarkson Alliance Stewart Hackney, Business Development Manager, Fusion Building Systems Jack Kennedy, Construction Director, Charcon Construction Solutions Working Group support: Shelagh Grant, Chief Executive, The Housing Forum shelagh.grant@housingforum.org.uk Laura Waind, Membership & Development Manager, The Housing Forum laura.waind@housingforum.org.uk The Housing Forum is grateful to The Hyde Group for supporting the report and facilitating this examination of the role of OSM in contributing to the debate on housing supply. With special thanks to David Gannicott, Group Director of Business Development and Simon Vevers, New Business and Strategy Director at The Hyde Group. Printed by Hartgraph Ltd. The Housing Forum Working Groups produce influential reports for our members, which are recognised at the highest levels in Government and throughout the industry. The topical agendas continue to draw in external specialists from finance, planning, Government and trade associations. Member organisations can join any Working Group and to register your interest in participating, please contact Shelagh Grant or Laura Waind. shelagh.grant@housingforum.org.uk laura.waind@housingforum.org.uk


More Homes Through Manufacture A Housing Forum Working Group Report Contents 3 Contents 04 06 08 16 18 24 26 42 44 46 Foreword David Lunts, Executive Director of Housing and Land at the Greater London Authority on the challenge to build more homes for London Introduction Shelagh Grant, Chief Executive, The Housing Forum and David Gannicott, Group Business Development Director, The Hyde Group Why housebuilding is changing Innovative solutions needed to help solve the housing crisis Why wouldn’t you buy a factory home? HTA Design Partner, Rory Bergin runs through all the advantages Living in a factory made home Residents describe what it’s like From feeding the cat to ordering food Jim Martin, Senior Partner, Martin Arnold, explains why homes are set to get smarter Transforming construction Housing schemes around the country built offsite The digital revolution Andy von Bradsky, Chairman, PRP, on integrating digital technology and offsite prefabrication Concluding remarks Weighing up the benefits Credits

4 Foreword More Homes Through Manufacture A Housing Forum Working Group Report Foreword David Lunts Executive Director of Housing and Land, Greater London Authority and observer to The Housing Forum Board We need to build a lot more homes and we need to build differently to do so. That is obvious when you look at the challenges we face in seriously stepping up supply. Land shortages, skills shortages and materials shortages are all massive constraints and each points to the need for a step change in ways to deliver new housing - not least in embracing faster, better and more modern methods of construction (MMC), the benefi ts of which are highlighted in this report. But is the industry ready to embrace the new? It certainly won’t be easy. Some of the methodology is still unproven at scale and the jury is still out over cost effi ciencies, for example. But if we are serious about increasing the rates of house building - and to do so over the long term - we need to work harder to make this step change possible. There is certainly a role for the public sector to help in sponsoring and leading this change. It could, for example, become a condition to use responsible modern methods of construction as a condition of building on public land, and grant funded housing associations could come together to use their collective buying muscle to provide a steady pipeline of opportunities for manufacturers to invest in production technologies at scale. The new Housing Zones too, which have recently been launched to accelerate new housing in regeneration areas, could also provide useful opportunities to support MMC at scale. The industry is slowly adapting to new construction techniques and this should be welcomed. But far more can be done, and needs to be done, to embrace change at scale if we are to ramp up home building to the levels we need. This report is a useful and timely signpost in that journey.

5 The Oval Quarter. South London, built using modern construction methods (see page 29)

6 Introduction More Homes Through Manufacture A Housing Forum Working Group Report Introduction Housebuilding is changing. An urgent need for more homes, coupled with a shortage of those skilled in traditional trades, is driving housing innovation. Encouraged by Government, housebuilders and housing associations are turning to more modern methods of constructing homes, increasingly building key components in factories and assembling them on site. Our aim at The Housing Forum – which draws expertise from Shelagh Grant, Chief Executive The Housing Forum all those involved in design, building and developing housing – is to help build more and better homes and that is why we are delighted to work with one of the leading housing providers, The Hyde Group, to explore, capture and celebrate these exciting developments in housebuilding. The Housing Forum, in its 2015 Call for Action, said, “Britain urgently needs a new strategy to build more homes, invest in the existing housing stock and overcome a capacity and skills defi cit which is threatening to create a barrier to increasing supply. But we must ensure that increasing output is not at the detriment of quality. If we are to leave a lasting legacy for future generations, we must innovate to drive the highest standard of design and performance in new and existing homes.” We don’t pretend for one second that offsite technology is the only answer to solving the housing crisis, but it can play a much greater part and should be developed and nurtured. The resulting homes can be of a higher quality, more comfortable and warmer than traditionally constructed homes, and of course, built far more quickly. This report provides a useful commentary on new types of construction for housing, dispels a few misconceptions and advances the debate on how offsite manufacture can move into the mainstream. We hope consumers and housing professionals alike will fi nd it useful, interesting and inspiring.

7 Homes in Coventry built for Orbit housing association using factory-built timber frame panels (featured on page 18) Hyde and modular construction David Gannicott, Group Director of Business Development, The Hyde Group We believe that modern methods of construction, in the form of modular or offsite building, has the scope to reduce build costs and improve quality standards. Hyde has ambitions to deliver at least one such scheme during 2015/16. Given the shortage of labour skills especially in London and the South East, we are keen to work with contractors using modern methods of construction, especially on low cost rented or schemes for the private rented sector. In fact, we have designed our new contractor framework to encourage modern methods of construction. We are delighted to be working with The Housing Forum in its research to promote modern methods of construction as we believe that all of the economic factors are in place to make it a success this time round.

8 How House Building is Changing and Why More Homes Through Manufacture A Housing Forum Working Group Report HOW HOUSEBUILDING IS CHANGING AND WHY SKILLS SHORTAGES AND GREATER ENERGY EFFICIENCY ARE DRIVING INNOVATION University accommodation, like these new Mayfl ower Halls at the University of Southampton are built using prefabricated components, and housebuilding is beginning to follow


10 How House Building is Changing and Why More Homes Through Manufacture A Housing Forum Working Group Report he number of new homes being built in the last few years has fallen to the lowest on record – fewer than half the number the UK needs to be producing to reduce housing shortages and bridge the huge affordability gap. A survey from the National Housing Federation last year pointed to the consequences – three out of 10 parents have at least one adult child, aged between 21 and 40, still living with them at home, mostly because their son or daughter cannot afford to rent or buy their own place. But as housebuilders and housing associations begin to increase the building of new homes they are turning to more modern methods of construction to build faster, to higher standards, and to enable them to comply with more stringent demands for greater energy efficiency and therefore lower energy bills. While housebuilding has remained persistently traditional, in that the most common building method involves using a structural inner skin of concrete blocks covered in an outer skin of brick, we are increasingly seeing an array of factoryfabricated components even in traditionally built homes, such as timber roof trusses and timber frame walls. Many other building types – from student accommodation to offices to schools and hospitals – have been using more and more components produced in factories and assembled on site. Housebuilding is now increasingly turning to offsite manufacture for a number of reasons: > Offsite methods offer advantages in terms of speed of construction on site, quality of build, sustainability and reduced health and safety risks. Less labour and fewer materials and deliveries are needed on the construction site, meaning a reduction of noise, disruption, dust and waste created for the local area. > Increasing the energy efficiency of new homes through tightening requirements of Part L of the building regulations is another key driver. It will become more difficult and therefore more expensive to deliver through traditional forms of construction. > Skills shortages – according to Offsite Housing Review, housebuilders said that to increase build capacity to more than 140,000 homes a year they would need to turn to some form of offsite1 . Build rates of 230,000 a year are needed to meet demand. A shortage of traditional tradespeople like bricklayers – and the recent shortages of bricks – has also pushed up prices of building in a traditional way, so that offsite methods are more commercially viable2 . > Offsite manufacture dovetails with the needs of those developing for private or social rent where the financial model relies on faster construction and occupation. At the moment, about 90 percent of all new housing in England and Wales is constructed using masonry – brick and block. The inner skin provides the structural walls that bear the load of the intermediate floors and roof above. Blockwork, set in mortar, has been the

11 Light weight steel frames, as used by Osborne to build Brunel Hall, a low cost housing scheme for Crawley Borough Council, are becoming increasingly popular in housebuilding most popular way of building homes in England and Wales since the 1930s. The work is traditionally done by bricklayers, who build both inner and outer skins of the cavity wall. Much of the remaining 10 percent of new housing uses timber frame (which accounts for about 70 percent in Scotland). The small remaining portion is built using what are known as Modern Methods of Construction (MMC) where a significant proportion is built in a factory. Timber frame construction is very well established and considered more or less traditional, even though much is factory made. Masonry construction has remained Using Fusion Building Systems offsite technology meant that this student accommodation for Oxford University could be delivered quickly the most popular for a number of reasons, but a lot of it is to do with costs. It’s been more economical. But as labour costs have risen and traditional construction has become more expensive, the balance is tipping, particularly as demand rises for alternative methods. As factory production is scaled up, it is anticipated that costs of building using offsite prefabrication construction will fall. That’s not to say it’s a foregone conclusion with housebuilders still preferring traditional construction for a number of reasons, which we’ll get on to later. However, the Government is certainly encouraging greater use of offsite construction to increase housebuilding and recently awarded a £22m grant to a major construction company, Laing O’Rourke, to invest in new technology. The contractor’s offsite ‘kit of parts’ construction system, Design for Manufacture and Assembly (DfMA), was used to deliver the Leadenhall Building, also known as The Cheesegrater, in the City of London. It was also used to build around 70 percent of the UK’s first privately funded council housing Why investor L&G is backing offsite construction — Legal & General has invested over £1 billion in building new student accommodation over the last three years and has used a variety of offsite manufactured components in the new buildings, including bathroom pods. It is now looking to use this building method as it extends its property portfolio into the private rented sector. It aims to grow this portfolio to well in excess of £1bn over the next five years across the UK. James Lidgate, Head of Residential, at L&G says: “We’re keen to harness modern methods of construction for a number of reasons; it provides better quality, and meets higher sustainable credentials whilst delivering lower operating and lifecycle costs.” It has committed plans to date for £200m of development, with buildings set to be between four and 10 storeys. 1 Professor John Miles, University of Cambridge and Professor Nick Whitehouse Oxford Brookes University, Offsite Housing Review, February 2013, commissioned by Department for Communities and Local Government, published by the Construction Industry Council 2 According to a report by accountants KPMG and the London Chamber of Commerce and Industry (LCCI), about 20% more construction managers, surveyors, electricians and other trades will be needed to meet demand, over the next four years, than were needed from 2010-13. November 2014

12 How House Building is Changing and Why More Homes Through Manufacture A Housing Forum Working Group Report scheme in Barking and Dagenham. Laing O’Rourke has ploughed millions into developing its prefabrication factory near Worksop, which is currently developing DfMA prototypes that utilise more lightweight modular steel frames and a range of alternative cladding options3 . Elsewhere, procurement organisation http://www.constructionmanager.co.uk/news/laingorourke-ramp-offsitesolution-housing-crisis/ ( http://www.insidehousing. co.uk/sectors-first-housebuilding-factory-movesstep-closer/7008182. article?adfesuccess=1 http://www.insidehousing. 3 July 2014) 4 Procure Plus is planning to create the first offsite factory dedicated to social housing, which could see up to 1,000 homes produced in the North West of England each year from 2016. According to a report in Inside Housing magazine4 , Procure Plus has engaged (February 2015) 5 co.uk/development/sociallandlords-increase-use-ofoffsite-methods/7008558. article ( March 2015) consultants to assess the viability of developing the pre-fabrication assembly plant, which would cost £2-3 million to construct, to produce homes for the 40 local The different types of offsite manufacture — Offsite manufacture is a catch-all term to describe technology where a component or a significant proportion of a house is built away from the site – usually in a factory. From the outside, homes built using these techniques may not look any different to traditional homes, as they may still be clad in a brick ‘slips’. Volumetric: These units are 3D modules assembled in a factory. The term ‘modular’ or ‘pods’ is used to describe load-bearing units. The main market for volumetric is for closed modules. One of the main advantages is that these can be whole rooms that come fully plumbed and wired which are transported to site and stacked on top of each other on ready laid foundations, to form the building. This method is popular for highly standardised accommodation such as hotels, student residential halls and care homes and flats in urban medium and high rise situations. Mar City is a developer which uses steel framed volumetric units which are fully kitted out with kitchens and bathrooms and transported to site. The modular units or pods may just be bathrooms. With pods the big advantage is that services installation is transferred into factory engineered conditions. For example, more than 30 trade activities are transferred off-site when bathroom pods are used. This leads to fewer people on site, easier commissioning and less rework. Panellised: Increasingly popular in the construction of housing is the use of panellised systems. These systems involve the on-site assembly of flat panel walls to form the internal load bearing element, and cassette floors (again a floor panel) and roofs. Systems range in complexity from simple timber or light steel panels (open), or concrete panels and cassettes, to more complex factory-finished units incorporating insulation, lining, doors, windows and services distribution (closed panels). Closed panel construction is the logical step up from standard open timber frame manufacturing, as the insulation, plaster board and electrical systems are installed offsite within the panels before delivery to site allowing the unit to be wind and watertight in one day. A major innovation in recent years, which is increasingly being used, is structural insulated panel systems (SIPS), where the rigid insulation core is bonded to sheet linings to form the panel. Cross-laminated timber (CLT) is also starting to make its mark. CLT panels normally form the structural floor and wall element of buildings, and have been used successfully to build up to nine storeys in the UK. It is typically used in offsite manufactured panels delivered to site for erection via crane. Cross-laminated is formed in a similar fashion to the more familiar gluelaminated timber beams (‘glulam’), using small sections of timber bonded together with permanent adhesives with the grain perpendicular, resulting in structural strength across two dimensions, and improving structural integrity and dimensional stability. As well as aiding speed of construction panellised systems offer flexibility in terms of layout and room size. The integration of Building Information Modelling in the production of systems, including those supplied by Fusion Building Systems, has enabled a degree of mass customisation to be achieved at relatively low volumes – giving housebuilders greater flexibility. Fusion Building Systems Business Development Manager, Stewart Hackney, told The Housing Forum that lightweight gauge steel has been gaining in popularity because it does not settle or shrink and provides a better thermal and acoustic performance. Housing can be constructed from hybrids of modular and panellised systems. The Housing Forum’s view is that it is essential to ensure that appropriate technology is chosen for appropriate sites. housing associations that form its client base in the North West. The magazine reported that the project is being monitored by the Homes and Communities Agency, which wants to increase offsite construction as part of its 2015-2018 affordable homes programme. Inside Housing also published a survey in March 2015 which found that 15 out of 17 major housing associations intended to increase their use of offsite construction, including timber frame and modular builds5 . The 17 associations together have a development pipeline of 22,544 homes over the next three years, for which 57 percent will utilise “offsite techniques”. Most of the associations cited advantages in terms of cost, build quality, speed of delivery, fewer weather delays, improved energy-in-use and smaller carbon footprints.

13 Jim Martin, Senior Partner, Martin Arnold, who chairs the The Housing Forum’s Working Group, Smarter Supply: Smarter Resources, says: “MMC invariably produces higher quality, because these homes are built under cover in benign conditions. A year ago, using offsite systems was more expensive, but this year the cost is the same. However, these systems bring the benefit of speed, and by next year they could be cheaper.” The sentiment is echoed by contributors to our technical case studies beginning on page 27. Though rising costs of labour and materials, coupled with increased capacity and Government support, is helping drive momentum for more use of offsite manufacturing, there are still barriers to be overcome for the various technologies to become mainstream amongst the major housebuilders. The Offsite Housing Review found that there were a number of factors holding offsite back, views shared by members of The Housing Forum, who have been discussing how offsite manufacture can become more mainstream in housebuilding. These include: Who pays upfront costs for the factory units. Procuring units fabricated in the factory requires upfront payment, which runs counter to traditional practice in that housebuilders will generally subcontract a lot of the work and then pay for it after it’s been completed. Public perception of poor quality product. Historic problems have blighted the ‘prefabrication’ brand. There is concern about systematic failure. Just because it’s been built well in the factory does not mean the units will be put together well on site. And if there is a problem, this could be amplified. Confidence in the product and process. While system certification is addressing concerns of insurers and funds and mortgage providers, product life and whole life performance continue to be major concerns. The Meadows, Essex University built by Bouygues UK. Images by Hufton+Crow Offsite manufacture in university accommodation — Offsite prefabricated units have long since been used in university accommodation for students; they provide examples for housebuilders to learn from. Mayflower Halls (shown on page 8 and 9) at the University of Southampton comprises three residential tower blocks over a 1.5 acre site reaching up to 17 storeys high, positioned around a central piazza. The £42.6m scheme was completed in September 2014 in 20 months and was constructed using reinforced concretre frame with SIP infill panels. 8,000 plus square metres were installed per week of programme. Principal partners: Architecture PLB (architects), Osborne (contractor), Innovaré Systems (designer), Innovaré Systems (manufacturer) and the University of Southampton (client). The Meadows, at the University of Essex in Colchester (shown above), is a 15,826 sq m student complex providing accommodation for 648 students. It comprises 19 town houses for 228 students plus ensuite cluster flats for a further 420 students. There is also a social pavilion housing a common room, a launderette and a convenience store. The total cost was £23m with an average cost per unit of £35,000. Completed in September 2013, a mixture of construction techniques were used – including ensuite bathroom GRP pods, in situ concrete frame (three blocks – five to seven storeys high) and timber frame townhouses. The developer was Uliving, a consortium made up of Bouygues Development, housing provider Derwent Living and investment company Equitix. Principal partners: Bouygues UK (contractor), Lewis & Hickey (architect), MLM (structural consultant), Kane Heating (mechanical contractor) and INEO (electrical contractor), Altor (pods supplier) and Stewart Milne (timber frame manufacturer and installer).

14 How House Building is Changing and Why More Homes Through Manufacture A Housing Forum Working Group Report Bathroom pods arrive on site for the Riverlight development in Vauxhall, London (see case studies page 36) Development of new skill sets. Clients and project teams need to understand the properties and constraints of the selected system and the revised project process. The whole project team also needs to collaborate effectively. EU procurement rules make it difficult to get an offsite supplier involved earlier on in the process. That said, cost is often a determining factor in choosing the form of construction and if production could be increased and with it costs lowered, the balance could tip more favourably in offsite’s favour. To increase demand, an incoming Government could use plans for new garden cities to promote offsite manufacturing to build homes. That way, demand would increase and encourage more investment, which could bring down costs. Another suggestion is for Government to stipulate that publicly owned land being sold for development could include an element of offsite construction. However, there are fears that this would depress the sale price and be impractical to enforce. With growth anticipated in both housing and public sector construction, offsite manufacture is expected to play an important role in providing additional capacity.

15 De-bunking myths about factory manufactured housing — Getting a mortgage In the past it has sometimes proved difficult to obtain mortgages and insurances on homes built in a non-traditional way. This was due in part to the relatively poor track record of past generations of nontraditional construction. Attitudes have changed somewhat as products have improved and certification systems put in place which can demonstrate quality and longevity. The Council of Mortgage Lenders (CML) says on its website: “While lenders have no intrinsic preference for any particular mode of construction, they do have one overriding requirement: that properties considered in relation to a mortgage must be capable of standing as security for a loan of up to 35 years.” Says the Council: “In practice, this means that the property must be saleable and maintain, or increase, its value over the term of a mortgage loan.” In relation to modern methods of construction, lenders have been concerned about the ability of some designs to meet this criterion in key respects: — Durability: achieve a design life of at least 60 years. — Whole life costs at a level comparable to traditional construction: particularly relevant for lenders to social housing providers. — Repairability: no undue repair costs, and ability to use a range of local repair services. — Adaptability: the property should, without difficulty, support the usual range of adaptations/ extensions such as a porch and conservatory. — Insurability: buildings insurance should be available on normal terms. The CML flags up a number of certifications systems including those from the British Board of Agrément (BBA), the BRE and BOPAS. In addition, following a rigorous technical assessment to ensure fit for purpose and a 60-year design life, the NHBC will provide a 10-year warranty for non-traditionally built homes. Given this is the leading new build warranty scheme in the UK, developments that have this warranty are unlikely to struggle for a mortgage, nor should an owner struggle to sell on, says the NHBC’s Head of Standards and Technical, Graham Perrior. The BBA’s assessments of building systems or MMC, for example, focus on the demands of UK building regulations and also pick up any nonstatutory requirements, such as those of the NHBC. There are Agrément Certificates for building systems which include steel and timber framed, structural insulated panel systems, insulated concrete formwork and composite structures. Meanwhile, the Buildoffsite Property Assurance Scheme (BOPAS) has been developed by Lloyd’s Register, Building Life Plans (BLP), The Royal Institution of Chartered Surveyors (RICS) and Buildoffsite, in consultation with the Council of Mortgage Lenders and the Building Societies Association. The scheme was developed following consultations with the main UK lenders to address their perceived risks in lending against non-traditional construction systems. BOPAS comprises a rigorous durability and maintenance assessment and process accreditation, supported by a webenabled database which gives access to details of assessed building systems, registered sites and individual properties which have been warranted under the scheme. The data base not only holds information relating to first sales after construction but will be accessible for the life of a property, allowing all subsequent sales to be similarly checked against the database (www.bopas. org). Terry Mundy, UK Business Development Manager, Lloyds Register EMEA, stated that the BOPAS process, supported by the insurance based 10-12 year warranty, was acknowledged by the principal lenders as mitigating their perceived risks associated with lending against non-traditional construction systems. And the transparency afforded by the BOPAS web-based data base provided valuers with the confidence to accurately value non-traditional properties listed on the data base and supported second hand values tracking the market mean. A number of those involved in factory-made housing say that finance has not been a issue. Mar City, a housebuilder specialising in modular offsite construction techniques, told us: “Mortgages are fine; people have moved in on a number of our sites and have building insurance and NHBC warranty. Our homes have sold well.” PRP Chairman Andy Von Bradsky, architect of the Oval Quarter in Lewisham,one of our case studies, said: “The new houses have been very well received by returning residents and on the open market. There have been no bad perceptions about offsite production as they are traditional in appearance.” Getting insurance A potential drawback of using modern methods of construction is the perception that insurers can be reluctant to offer cover, particularly for timber frame construction. However, the NHBC’s Graham Perrior, says, “There should not be a problem getting buildings and contents insurance with the proviso they are designed and built properly. Timber frame housing should present no more fire risk than masonry construction. Arguably, there could be more risk during construction in that the timber can be exposed, but significant work has been carried out over recent years to reduce this risk and once completed it is fully protected.” Extending the property A concern flagged up by some homeowners is whether homes built offsite with prefabricated methods provide the same degree of flexibility to extend as those built using traditional systems. Volumetric systems can be more difficult in terms of flexibility to extend, but panellised systems should be no more difficult than conventional construction, says Fusion Building Systems’ Business Development Manager Stewart Hackney

16 Expert Opinion Rory Bergin More Homes Through Manufacture A Housing Forum Working Group Report EXPERT OPINION: WHY WOULDN’T YOU BUY A FACTORY BUILT HOME? MANUFACTURED HOUSES WILL ALLOW CONSUMERS TO CUSTOMISE THEIR HOUSES, SAYS ARCHITECT RORY BERGIN here are many good reasons why new modern homes should be made in a factory. There are no good reasons why they shouldn’t. Practically everything else we use in our lives comes from a factory and we are very happy with them. We expect our cars, TVs, computers and phones to be mass-produced, and would be very surprised to fi nd that they weren’t. In fact we wouldn’t buy them if we found that they were hand-made by a group of people brought together in a muddy fi eld and given instructions in a language not their own, and chosen because they provided the lowest price, or just happened to be available that day. That’s how a lot of housing is currently constructed in the UK. Manufactured homes are more likely to meet the stringent quality standards demanded by regulations for new homes because it’s much easier to check quality when the product is being made in a warm building, out of the wind and rain. Workers of all ages and backgrounds can be employed in a factory because they are not expected to carry heavy loads up ladders, or withstand the cold. So the workforce can be from a wider demographic and different backgrounds. In the current economic conditions this factor is lowering the cost of building homes in a factory as wages for fully employed people are stable. The selfemployed sub-contractors who do much of the work on traditional building sites are raising their wages as much as possible because they can. In the rush to build homes, there is a shortage of labour such as bricklayers and carpenters, so the ones that are available can charge more for their skills. Factories are less exposed to this wage infl ation because their workers are permanently employed and therefore can’t demand increases in their wages at short notice. Factory owners tell me that last year, their homes were more expensive to build than traditional buildings, but could be built more quickly. This year they can be built for the same price, but more quickly, and next year they will be cheaper to build, and more quickly. There is a further promise of factory production which is the expectation that someday we will be able to order our home online and change the design to suit ourselves. If this sounds far-fetched, they have been doing this in Japan for decades. Companies with familiar names like Toyota have constructed tens of thousands of such homes for their customers, most of which have been customised to some degree. Factories with a high degree of automation can cope with a change in design easily, provided that the robot can be given the correct template to use; it doesn’t care if it does the same job ten times a day, or ten different jobs. The key element is that the robot is given a template to work from. Customisation does not mean that the customer can have what they want in every case; it means they can choose from a wide range of features, which ensures that no two houses are ever the same. It only takes nine variants in a house design to produce over 300,000 different homes, so customers can be satisfi ed that they have a unique product and the factory can continue to produce a unique design from relatively standardised components. There is a reason why the difference in quality between a factory-made home and a traditionally built home is not obvious to the average housebuyer or renter. No-one tells them, and the quality difference is not refl ected in the sales price. We have the ridiculous situation where the location and number of bedrooms in a property sets the value, and the quality of the fi nished home counts for

17 nothing. If a housebuilder does a very good job of building a traditional home or a bad job, it makes no difference to the price. If the home is hard to heat or very effi cient, it may be interesting to the purchaser, but it makes no difference to the price. If the three bedrooms of one property are bigger than the three bedrooms of the other, it makes no difference to the price. In a market like this it is very diffi cult for a housebuilder to concentrate on a quality product, since it makes no difference to his profi ts. We are trying to change this by introducing a way that purchasers and renters can see the difference in the quality of their new home. By creating a Home Performance Labelling tool, The Housing Forum is enabling people to rank the potential purchases in order of size, if that’s what they care about, or energy effi ciency, price per square metre, daylight, or maintenance costs. This way of making a purchasing choice is familiar to anyone who has bought a car, insurance, phone, electricity or a fridge in recent years. We think it’s time that such a tool was available to the housing market. By helping people to make their choices based on quantitative information as well as qualitative information we expect to drive up the quality of new homes in the same way that comparison shopping has driven the market in electronic goods. The product of tomorrow would be better than the product of today and offered at the same price. This is how markets should work. There should be room for low quality products and high quality products, at different price points, but the housing market currently values both products in the same way, leaving no room for quality. Because price is also set by location the current pricing system keeps the housing quality low in poor areas and reduces the likelihood of regeneration. Finally, in order to deliver anything like the number of homes we need, the housing industry in the UK must double in size. Output is currently about half of what we need to sustain the market. This growth won’t be achieved by adding more workers from abroad, working in muddy fi elds at low productivity levels. It will be achieved if we create a functioning offsite manufacturing sector, distributed across the UK, using a well-organised workforce, operating in a market where higher quality products get the sales prices that they deserve. Rory Bergin is a Partner at HTA Design LLP, which is a member of The Housing Forum The Hanham Hall development in Gloucestershire designed by HTA

18 Living in a factory built home More Homes Through Manufacture A Housing Forum Working Group Report LIVING IN A FACTORY BUILT HOME ATTRACTIVE PROPERTIES WITH LOWER ENERGY BILLS ARE SOME OF THE BENEFITS OF LIVING IN A FACTORY BUILT HOME, SAY RESIDENTS PHOTOGRAPHY: ED TYLER Natasha Devlin pictured in her new Passivhaus home in Coventry


20 Living in a factory built home More Homes Through Manufacture A Housing Forum Working Group Report “Thanks to the home being so well insulated and having the air filtration system, my eldest no longer has asthma.” Natasha Devlin, John Rous Avenue Coventry “When we found we had been successful in bidding for a house with Orbit, we drove round to have a look immediately,” says Natasha Devlin. “I was jumping up and down in the street when I saw the place. My first impression was that it is a lovely property on a great size plot. I was very happy.” Key building details: Building type: Passivhaus constructed using factory-built, timber frame panels by Beattie Passive Number of homes in scheme: two Client: Orbit Group Development time: 30 weeks. Roughly the same time as would take for a traditionally built home Development cost: £1,430/m2 for a home built to the German Passivhaus standard. Usual cost for such a property is £1,800/ m2, although Orbit had hoped to do it for £1,100/m2. A home built to Code for Sustainable Homes level three would cost £1,000/ m2 Date of completion: October 2013 Who lives here: Resident: Natasha Devlin, partner and two daughters aged 12 and 7 Type of tenure: social rent of £128 a week Lived there since: November 2013 Number of bedrooms: three Occupation: housewife Ms Devlin was unaware at first that the house was one of two built by housing association Orbit Group as part of a pilot project to explore the use of offsite manufacturing techniques to construct homes built to the highly insulated German Passivhaus standard. “When I found out it is a Passivhaus, I felt absolutely brilliant,” she says. “My children have asthma and we had been living in an old private rented property in Coventry that was much colder and draughty. As a result we had the heating on almost the whole time and this was terrible for the girls as it dried the air out and really affected their asthma. “Now, thanks to the home being so well insulated and having the air filtration system, my eldest is no longer classed as suffering from asthma and the youngest is far better too. They both used to suffer from eczema and that has gone right down as well,” Ms Devlin adds. The family’s cost of living has also dropped substantially. Rent has fallen from £650 a month in their previous private rented home to £512. Ms Devlin says she was spending £40-£60 a week on electricity and gas, but that this has now fallen to £150 a month at most. John Barnham, Head of Sustainable Investment at Orbit Group, says that although Orbit is pleased with the scheme, it has not yet built any further projects using off-site manufacturing techniques in its 1,000-home a year development programme. This is because it is conducting a review to see what is a realistic cost for an OSM development before it commits to further schemes. Mr Barnham adds that, while maintenance issues to date have been no different to those he would expect on a traditionally built project, there has been a “real learning curve for staff and tenants over the use of the mechanical ventilation kit and generally ensuring the air-tight membrane of the home is not punctured by drilling holes for pictures or to install Sky TV.” He says Orbit has provided a junction box for satellite or cable TV that avoids the need to drill holes and that residents are informed of this. Ms Devlin says she would definitely recommend the home to her friends. “They are all very envious of the quality of where I live and have all commented on it. We’re really happy here and would give it 10 out of 10.”

21 Neil Crowther, Shepherdess Walk Islington, North London “We used to live nearby in private rented accommodation in Hackney and were first attracted to living here by the fact we had some friends who have lived locally since 2002 and they love it,” says Neil Crowther, a resident of the award-winning Shepherdess Walk development since August 2006. The fact that the development – the first of its kind in the UK and built by Peabody owing to frustration at the length of time and cost of traditional methods – is made from factory-built modules stacked on top of each other was simply not an issue for Mr Crowther and his partner. “When we were thinking about moving here, we liked the fact it is an attractive building – especially the balconies, the wood cladding and the lovely external courtyard. We also liked the fact that Shepherdess Walk is run by a housing association, not a private landlord,” he says. As a long time resident of the east London borough, Mr Crowther also relishes the fact that, despite its location, the property – also more popularly known as Murray Grove – is cheaper than others nearby, yet provides generous accommodation. “The location is great for us in central London, five minutes’ walk from Shoreditch and Clerkenwell. Yet it is surprisingly peaceful. The flat is spacious and bright and lets in a huge amount of light.” Mr Crowther adds that, although his home has no gas central heating, it warms up quickly when needed and fuel bills are low as a result. He does express some concerns about the quality of the insulation on the external walls, however, saying the relevant rooms can feel noticeably colder than others. This may reflect a concern identified by Peabody in the build process that, although the 74 modules were factory-built in 12 weeks and erected on site in 10 days, much of the remaining build time was taken up by protracted efforts to satisfactorily clad Shepherdess Walk and construct the balconies. Although generally very happy with the internal finish of his home, Mr Crowther suggests the 16-year-old building is experiencing some wear and tear and that fixtures and fittings such as curtain rails are not as easy to replace as might be the case for a more traditionally built home. For Nick Hart, a neighbourhood manager at Peabody with responsibility for Shepherdess Walk, the block is a “joy” to maintain. “It simply does not suffer from the noise and other complaints that are common in others,” he says. “I expected it might have noise transmission problems due to its design, but that simply hasn’t been the case.” Mr Crowther says he would live in a modular home in future, but that, at present, he and his family are looking to move somewhere bigger as this isn’t an option at Shepherdess Walk. He adds: “It works really well for young people starting out and for us it was ideal.” Key building details: Building type: factory-built modules by manufacturer Yorkon Number of homes in scheme: 16 onebedroom flats and 14 two-bedroom flats Client: Peabody Development time: 44 weeks (including 17-week delay due to external works over-running), versus 62 weeks for similar development at nearby Dalston Lane using traditional techniques Development cost: £2.9 million and £77,800 per home, versus £2.7 million and £76,200 per home on Dalston Lane Date of “When we were thinking about moving here, we liked the fact it is an attractive building.” completion: November 1999 Who lives here: Resident: Neil Crowther, partner and oneyear-old daughter Type of tenure: keyworker rent Lived there since: August 2006 Number of bedrooms: two Occupation: public policy consultant, based at home

22 Living in a factory built home More Homes Through Manufacture A Housing Forum Working Group Report Peter Webb Beechdale Estate Walsall “We were living nearby in private rented accommodation and paying an astronomical rent of £700 a month before moving here,” says Peter Webb, who now rents a brand new, three bedroom detached home in Walsall from Accord Group. “The fact it is a factory-built house was not a factor in our decision to come here as we didn’t know when we applied for a home. When we were offered a home and when we did find out it was a timber property, we were initially very worried – it was effectively a wooden shed,’ he says. Peter and his family had never previously lived in a home built using modern methods of construction and were concerned about how robust the property would be. However, he says: “When we saw the house we instantly took a liking to it. Once you go inside, you cannot tell they are wooden houses – you just can’t. The rooms are more than big enough and the finish is lovely. Our friends come round and say ‘it’s all wood’, but I say ‘come inside’ and people are really impressed.” Another aspect that has pleasantly surprised Peter is the difference in his energy bills compared to previous homes. “It is amazing how much lower they are.” Peter and his family used to spend around £360 a month on gas, water and electricity. Now they spend £80 a month, quarter of their previous energy expenditure. This is music to the ears of Alan Yates, Director of Regeneration at Accord Group: “It’s incredible really, the savings our residents can make and it is great for everyone – especially those on low incomes.” Key building details: Building type: Factory-built, ‘closed’ timber panels by Accord’s LoCal Homes factory Number of homes in scheme: 40 Client: Accord Group Development cost: Just under £1,000/ m2 for a Code for Sustainable Homes level four home, a 20 per cent saving on cost for a home built to Code for Sustainable Homes level three using traditional methods Date of completion: January 2015 Who lives here: Peter Webb, wife and two adult children Type of tenure: Affordable rent of £115 a week Lived there since: January 2015 Number of bedrooms: three Occupation: Motorway maintenance supervisor Mr Yates says Accord has been building homes from the LoCal Homes factory it owns in Walsall for four years and half its 300 new homes a year are supplied by the factory’s 20 locally based staff. The aim is to increase this to 200 a year and to boost production to 400 homes annually overall by working with new clients such as Rooftop Housing Group and Stafford and Rural Homes. He says Accord runs the factory – the first of its kind by a UK housing association – as it creates jobs in its communities and costs a fifth less than traditional building techniques for a better quality home. “To maintain, there is really no difference to a traditionally built home,” Mr Yates says. “We go for a fabric-first approach with loads of insulation to ensure energy bills are low and there is no need for lots of other expensive kit.” Accord Group has sold 70-80 LoCal Homes on the open market too, with plans to do more. “Overall we are loving our home,” says Mr Webb. “I work nights and so have to sleep during the day. Despite the fact some homes are still being built nearby, you can’t hear a thing. I give this home nine out of 10 and would definitely recommend it to anyone.” ” Peter’s energy bills are now £80 a month. He used to spend £360 a month.”


24 Expert Opinion Jim Martin More Homes Through Manufacture A Housing Forum Working Group Report EXPERT OPINION: FROM FEEDING THE CAT TO ORDERING FOOD JIM MARTIN EXPLAINS WHY HOMES ARE SET TO GET SMARTER e are at the beginning of a revolution in the way we live in our homes. The internet, mobile devices and greater connectivity will give us the ability to live and manage our homes in an entirely different fashion. In 1975, only a tiny percentage of homes in the UK had gas central heating; 40 years later almost all UK homes are centrally heated, mainly by gas. Notably, central heating has changed the way we live and manage our homes. In the same way, smart home technologies provide the opportunity for a similar revolution. Within the next 40 years, a large proportion of homes in the UK will have ‘smart’ home elements. The defi nition of a smart home is generally agreed to be: “A dwelling incorporating a communications network that connects the key electrical appliances and services, and allows them to be remotely controlled, monitored or accessed.” Remotely in this context can mean both within the dwelling and from outside the dwelling. There are three things a home needs to make it smart: Internal network – wire, cable, wireless Intelligent control – gateway to manage the systems Home automation – links between products, services and external systems A key advantage of using smart home technology is that homeowners are given more control over their appliances and devices. For example, a smart home boiler can tell you when it needs servicing or is running ineffi ciently. The refrigerator may also be able to list its contents and order food. Using smart home technologies, devices can be connected to each other, which allows the passing of information to and from devices. A quick glance at their smartphones or tablets will provide the following information, when smart home homeowners are away: Did I turn the cooker off? Did I set the home alarm system? Are the kids doing their homework or watching television? Smart home technology is also known for home security features. The lights can be turned on and off to prevent burglaries and home intrusions – and in future the home will be programmed to water the garden or feed the cat. While it is exciting to think about this technical revolution, which is changing the way we live through greater connectivity, there are various practical applications of smart home technologies, not only home entertainment, clever security and energy management. As the population grows older, more home care will be required for many people. Remote monitoring and control are huge advantages in allowing elderly people to stay in their homes whilst using occupant monitoring, movement monitoring to detect falls and medication reminders to name but a few. A similar list could apply to infant monitoring or people with disabilities. Smart Homes technologies can be retrofi tted, they can be incorporated into a traditional build process but it is as a component in an OSM process that smart home technologies come into their own. In the same way a purchaser will select from a list of options when buying a car, a home purchaser will select from a range of smart options to be incorporated within the factory process. In fact, the application of smart home technology is limitless. Jim Martin is Senior Partner, Martin Arnold and Chair of The Housing Forum’s Working Group, Smarter Supply: Smarter Resources


26 Case studies Transforming Construction More Homes Through Manufacture A Housing Forum Working Group Report TRANSFORMING CONSTRUCTION HOUSING SCHEMES AROUND THE UK ARE BEING BUILT MORE QUICKLY USING OFFSITE PREFABRICATION TECHNIQUES AS ILLUSTRATED BY THESE 12 CASE STUDIES Offsite prefabrication was used extensively at the Olympic Way development in Wembley


28 Case studies Transforming Construction More Homes Through Manufacture A Housing Forum Working Group Report Case study 1 Showell Court, Wolverhampton Contributed by Paul O’Driscoll Wates Living Space paul.odriscoll@wates.co.uk Name of project: Showell Court Town or city: Wolverhampton Brief description: 64 apartment extracare home with communal facilities including sensory garden. Total cost: £7.2m Average cost per unit: £114,286 Principal partners: Wates (constructor), Pozzoni (the architect), DWP (services engineer) Stewart & Harris (structural engineer) Hemsec (the system provider) and Accord Housing Association (client). Completed: October 2009 Length of time to build: 60 weeks (further time would have been saved but for tolerance problems with precast concrete planks) Estimated time using traditional methods (from start on site ): 70 weeks Briefl y describe the construction method The offsite method involved the use of structurally insulated panels (SIPs) and precast concrete fl oor planks and stairs, externally clad in traditional brick work and look-alike copper cladding with a structural steel transfer slab with communal facilities. Erected using forklift. Why was this method chosen? Due to limited design available at tender we needed to delay the start on site to allow a fully co-ordinated scheme to be provided whilst still maintaining the critical end date for Accord. Changing from traditional to SIPs with precast concrete (PCC) planks allowed more time at the front end to complete the design and Accord’s brief. The use of PCC planks and SIPs also avoided the issues of overheating and excessive cooling plant often required with standard timber frame. Were there any additional/ unusual approvals needed and what were they? The SIPs and precast concrete fl oor were unusual and therefore an engineer was used to ensure that this composite system worked structurally. The engineer worked closely with the SIPs manufacturer and the pre-cast plank company on behalf of Wates to ensure this innovative structural solution met current regulations. We also needed to agree a new suite of bespoke Robust Details with Building Control and NHBC as this was the fi rst time this system had been used for residential developments. How did costs compare with traditional methods? Slightly more expensive for construction materials, however the preliminaries saving covered this extra cost. Would you use this method again? Yes What are your reasons? Speed and ease of build and because it provides a higher thermal mass which reduces overheating. Other comments on offsite manufacture for housing construction? The offsite components were a good quality product, manufactured in a quality environment. We still suffered design issues and perhaps if the use of BIM was employed, these design/sizing issues may have been prevented.

29 Case study 2 The Oval Quarter,Lambeth, South London Contributed by Rick Burgess PRP Rick.Burgess @prparchitects.co.uk Name of project: Oval Quarter, Lambeth (formerly Myatts Field Estate) Town or city: Lambeth, South London Brief description: 982 new homes in comprehensive PFI regeneration of Myatts Field Estate, Lambeth. The Oval Quarter consists of 134 houses, 160 maisonettes and 688 apartments, plus a new public park, community centre and new district combined heat and power system Total cost: £110 million (includes infrastructure, external works, community centre) Principal partners: Lambeth (client) in joint venture partnership between Regenter & Higgins Group. Higgins Construction (main contractor) PRP (architect) Length of time to build: Phase 1, 485 units in 23 Blocks completed in 24 months; Phase 2, 497 units in 11 blocks commenced Briefly describe the construction method Selected OSM system is light gauge steel (LGS) superstructure frame including prefabricated wall panels and floor and balcony cassettes. Why was this method chosen? All the known benefits of OSM, such as reduced onsite construction period, improved health and safety, increased quality, less waste, and overcoming the lack of on-site trade skills so fewer defects. Plus OSM offers very accurate system in terms of controlling geometry and tolerances. It significantly reduces foundation loads (and hence ground works costs). It avoids differential movement issues associated with timber frame. And it achieves significant acceleration in superstructure frame erection relative to traditional site based methods. In addition, the integrated design concept gives early technical input on design requirements for OSM system, thus embedding accuracy and deliverability in the planning design. So, many efficiencies derive from this rigorous approach. How did costs compare with traditional methods? We are awaiting advice on cost comparison. Would you use this method again? Yes. What are your reasons? All of the above, plus additional benefits realised through working collaboratively with Metek using BIM, such as high level of quality control during manufacture in factory and assembly on site; waste recycling in manufacture and reduction of on-site waste; and easier resolution of spatial ‘clashes’ such as clashes with hot-rolled steel elements prior to site . Any other comments on offsite manufacture for housing construction? The key reasons for success on this project are the early decision on selecting OSM system during the design stage, and excellent collaborative working between the client, constructor, design team and system supplier.

30 Case studies Transforming Construction More Homes Through Manufacture A Housing Forum Working Group Report Case study 3 Kirklees PFI, Huddersfield Contributed by Bev Grey Wates Living Space,East beverley.grey@wates.co.uk Name of project: Kirklees PFI Excellent Homes for Life Town or city: Huddersfield and Dewsbury Brief description: The project includes construction of three extracare housing schemes containing 140 new homes for older people and a further 291 one and two bedroom homes with 35 homes specifically designed for wheelchair users over 27 separate sites throughout the Kirklees area. Total cost: £69m Average cost per unit: £100,000 Completed: March 2014 Principal partners: Kirklees Council and Regenter Excellent Homes for Life Consortium,Wates Living Space (main contractor), Estimated length of time to build if using traditional methods (from start on site): 2 years, 9 months Briefly describe the construction method Pre-insulated open panel timber frame. Why was this method chosen? Greater predictability of programme delivery, taking brickwork off the critical path & reducing labour resource. Would you use this method again? Yes. What are your reasons? Predictability of time and reduction of critical labour resources. Were there any difficulties with the method chosen? Main issue is effect of inclement weather and control of moisture content which leads to requirement to allow drying out period within programme Watson Batty Architects & MET Consultancy(designers). Length of time to build (from start on site): 2 years, 3 months How did costs compare with traditional methods? Main benefit was the time saving, which allowed the client to maximize early rental income.

31 Any other comments on offsite manufacture for housing construction? Although not necessarily a cheaper method of construction, the use of timber frame makes for a more predictable delivery programme. It contributes to the simplification and standardisation of details to achieve a high standard construction, allowing both client and contractor a greater degree of confidence from the outset. Where there any additional/ unusual approvals needed and what were they? After the general election in 2010, the government asked for an additional value for money exercise as part of the sign off on PFI schemes. We were requested to produce a value for money assessment for the Housing Minister. This scheme exceeded the required standard and obtained the necessary sign off.

32 Case studies Transforming Construction More Homes Through Manufacture A Housing Forum Working Group Report Case study 4 School Mews, Hastings Contributed by Richard Barwick For Southern Housing Group richard@regeneration.uk.com Name of project: School Mews Town or city: Hastings Brief description – house types & tenure and number of units 15 new homes, all affordable rent Total cost: Part of £60k per plot competiton, total cost with abnormals and land: circa £1.5m Average cost per unit: £100k (approx) Principal partners: Southern Housing Group (client); developer SEEDA Completion: 2008 Length of time to build (from start on site ): 40 weeks Estimated length of time to build if using traditional methods (from start on site): 30 weeks (against 50 traditional) allowing abnormal groundworks( unclear) Briefly describe the construction method A mixture of timber frame/ steel frame/ volumetric/ timber finished fully insulated panels; triple glazed windows; pre-installed plumbing. Why was this method chosen? One of Design For Manufacture submission winners (second tranche) How did costs compare with traditional methods? 10 percent higher Would you use this method again? Yes What are your reasons? A proven German company with good track record and high quality system. Were any difficulties with the method chosen? Weberhaus demonstrated excellent thermal efficiency and air-tightness resulting in low carbon footprint and lower running costs. Unfortunately, Weberhaus now appear to focus on the one-off schemes, no longer affordable high volume schemes. Who are the principal partners? Southern Housing Group and Weberhaus with Radley House Architects Any other comments on offsite manufacture for housing construction? An enlightened client, using a recognised manufacturer and a good design team with the relevant experience is the best way to proceed. There are challenges, but these can be overcome. Were there any additional/ unusual approvals needed and what were they? Achieved Building for Life; Code for Sustainable Homes (4), Secured by Design, Housing Quality Indicators

33 Case study 5 Sampson Close, Coventry Contributed by Paul O’Driscoll Wates Living Space paul.odriscoll@wates.co.uk Name of project: Sampson Close Town or city: Coventry Brief description: Five two and three-bed terraced houses and 18 twobed apartments built using the Passivhaus approach Total cost: £3.5m Average cost per unit: £152,000 Principal partners: Orbit Homes (client), Wates Living Space (contractor), Baily Garner (architect), Stewart & Harris (consulting engineers) Length of time to build: 12 months Is the project complete? Yes When was it completed? Apr 11 Estimated length of time to build if using traditional methods: 14 months Were there any additional/ unusual approvals needed and what were they? Passivhaus certifi cation to ensure that all parameters set by Passivhaus were achieved, such as extremely low air leakage of 0.6 Briefl y describe the construction method Composite panel super structure (including windows and services) with 250mm of cellulose insulation, external brickwork, render and thermowood. Why was this method chosen? To ensure that the thermal qualities and low air leakage requirements were achieved. How did costs compare with traditional methods? High premium due to this scheme being an R&D type project. Not many manufacturers of specialist heat and ventilation product in the UK, if any, at the time and the frame and mechanical/ventilation equipment was sourced from Europe. Would you use this method again? Method of using Germanpanel system with pre-installed Passivhaus certifi ed windows is a tried and tested method on the continent. However, in the UK, this is expensive and still has risks attached. In Germany apartments are larger than apartments in the UK which helps with achieving the air leakage requirements, but it is more diffi cult in the UK. Preference to use traditional method of construction in the UK for cost reasons, although more diffi cult to achieve standards. What are your reasons? There are various methods which could be adopted, such as traditional build, the main factor being that building regulations in the UK requires air leakage at 7 (was 10 at the time), whereas a Passivhaus requires 0.6. Were there any diffi culties with the method chosen? Method chosen was the correct method, although there was not enough understanding of the design, which has a huge impact on the cost to build and the ability to achieve Passivhaus certifi cation. Properties need to be designed larger; products to cope with air movement need to be sourced from the UK; and robust methods for achieving air leakage need to be readily available in the UK. Any other comments on offsite manufacture for housing construction? Offsite manufacture allows the precision required, and the panel system used on this scheme was erected and water/weather tight within two weeks of being delivered to site. The frame and windows were nearly 50 percent of the scheme costs.

34 Case studies Transforming Construction More Homes Through Manufacture A Housing Forum Working Group Report Case study 6 The Greenhauses, West London Contributed by Kingspan Insulation technical@kingspaninsulation. co.uk Name of project: The Greenhauses, Brook Green Town or city: London Brief description: Thirty new homes, including eight for outright private sale, 13 for shared ownership and nine for affordable rent. The site comprises a row of three-storey terraces (Block A), two five-storey apartment buildings (Blocks B & C) and a further four mews houses with roof terraces (Block D). Both Blocks A and B have now been fully Passivhaus certified. Total cost: not supplied Average cost per unit: N/A Principal partners: Octavia Housing (client), Cartwright Pickard (architects), Durkan (contractor) and Kingspan Timber Solutions Briefly describe the construction method On Block A, a breather membrane was stapled to the outer face of the Kingspan TEK Building System (SIPs), followed by 90 mm thick Kingspan Kooltherm K12 Framing Board. A 50mm cavity was then left between the build-up and the 102.5mm brickwork facing. Internally an airtight membrane was taped to the Kingspan TEK Building System’s face, followed with a 25mm service zone and two 15mm layers of plasterboard lining. The Kingspan TEK Cladding Panels (SIPs) installed on Block B were fixed to the concrete floor slab using angled cleats. The buildup mirrored those in Block A with the airtight membrane sealed to the concrete frame and soffits with airtight tape. Why was this method chosen? Brick was chosen as the primary façade material for the buildings. Given the tight, urban nature of the site, minimising the thickness of the remaining wall build-ups, whilst still attaining the required level of thermal performance, was a key objective. SIPs ensure a predictable installation with minimal on-site waste. The proprietary jointing system featured on both Kingspan TEK products, in combination with the additional airtightness detailing on the project, ensured that air loss from the blocks is below the 0.6 air changes per hour @ 50 Pa. On average, these homes are anticipated to make significant savings on fuel bills (up to 90 percent in the case of the certified units).

35 Case study 7 Park Heights, London Contributed by Steven Busbey Wates Living Space steven.busbey@wates.co.uk Name of project: Park Heights (former Waylands House) Town or city: Stockwell, South London Brief description: Demolition of an existing 15 storey tower block and replacement with a 20 storey residential block, including a café facility. A total of 159 apartments consisting of 84 affordable and 75 private sales. External works include car parking and soft landscaped areas. Designed to Code Level 4 & Lifetime Homes. Total cost: £27.4m Average cost per unit: £172,000 Principal partners: Network Housing Group (client), Wates Living Space (main contractor),GCL (frame contractor), Conisbee(engineer), Oran Pre-cast (manufacturer) Completion: December 2015 Length of time to build (from start on site ): 100 weeks Estimated length of time to build if using traditional methods (from start on site ): 106 weeks Briefl y describe the construction method Offsite manufactured precast concrete frame elements, comprised pre-cast reinforced concrete structural columns, along with twin-wall core-walls and lift shafts were incorporated into a post-tensioned fl at-slab reinforced concrete frame to expedite the construction of the superstructure. The twin-wall system consists of two 65mm thick concrete leafs joined together by steel, lattice reinforcement to form a structural panel. Once the panel is positioned on site, it is fi lled with poured concrete. Why was this method chosen? Mainly to expedite the construction of the reinforced concrete frame through reduced Man hours, faster on-site construction times and reduced site labour and materials. It also allowed for high quality fi nish and control. How did costs compare with traditional methods? When assessed holistically and, whilst also taking into consideration the reduced labour, falsework and programme and prelims savings, this method was considered more cost effective than a traditional approach. Would you use this method again? Yes What are your reasons? Because of the benefi ts mentioned above Were there any diffi culties with the method chosen? No diffi culties but it does require a design input from the specialist via the reinforced concrete frame contractor which brings with it a need for good design management/ coordination Were there any additional/ unusual approvals needed and what were they? No unusual approvals. A review of the manufacturer’s design and calculations was undertaken by our structural engineer and a co-ordination review exercise was undertaken by our architect which would be the standard approach with any contractor design package.

36 Case studies Transforming Construction More Homes Through Manufacture A Housing Forum Working Group Report Case study 8 Riverlight, Vauxhall, London Contributed by Leona Eze Martin Arnold leze@martinarnold.co.uk Name of project: Riverlight Town or City: Nine Elms, Vauxhall, London Brief description: 116 units for shared equity ownership surrounded by private gardens and a new piazza, set on the bank of the River Thames Total cost: £17.5 Million Average cost per unit: Not supplied Expected completion: September 2016 Principal partners: St James, Berkeley Group (contractor), Viridian Housing (client), EPR Architects (designer); Bathsystem ( manufacturer) Martin Arnold (employer’s agent). Length of time to build (from start on site ): two years Estimated length of time to build if using traditional methods (from start on site ): 108 weeks Briefl y describe the construction method Offsite construction of bathroom pods were used for this development and included fi xtures and fi ttings and services ready for connection. Why was this method chosen? Delivering pods that are ‘fi t for purpose’ helped reduce the construction time, making the programme more effi cient and reducing our carbon footprint. The pods benefi ted from a high quality control within the factory enabled a high quality fi nish on the pods. How did costs compare with traditional methods? At present, the development is still under construction. Therefore, it is diffi cult to assess the cost-effi ciency savings in comparison to traditional methods. Would you use this method again? This method of modular construction is gaining momentum within our projects. What are your reasons? The method offers a range of advantages. Using offsite construction and producing the pods abroad helped minimise risks and health & safety issues. Producing materials in a factory enabled readily available materials to be transported to the new development. Fundamentally, this method is an effective modern method of construction, which produced a high quality fi nish. Were there any diffi culties with the method chosen No issues have currently been reported. Were there any additional/ unusual approvals needed and what were they? Using one of the main products of modern methods of construction, modules were selected for this project. Any other comments on offsite manufacture for housing construction? Adopting modern methods of construction, we developed bespoke bathroom pods to meet our client’s specifi cation requirements. The pods were manufactured ahead of time and shipped from mainland Europe before being craned into position and connected to the superstructure and services. The pods will add great value to this major regeneration development for the riverside community to enjoy.

37 Case study 9 Kidwell’s Estate, Maidenhead Contributed by Paul Inch Innovaré Systems paul.inch@innovaresystems.co.uk David Fish Wates Living Space david.fish@wates.co.uk Name of project: Kidwell’s Estate Town or city: Maidenhead Brief description: The mixed tenure scheme consists of apartment blocks providing a mix of one, two, three and four bed homes and a new communal space. Works consisted of the demolition of existing residential units followed by the construction of seven blocks across 3-5 storey height. In total, 204 units were constructed over four phases. Total cost: £26 million Average cost per unit: Not supplied Principal partners: Wates Living Space(contractor), Innovaré Systems (designer), Innovaré Systems (manufacturer),One Housing Group (client),Reddington(frame and groundworks), Clearwall (drylining) and Entric(electrical),Peter Taylor Architects (architect) Ramboll ( structural engineer) Length of time to build (from start on site): Works for phase one commenced in September 2010, with completion scheduled for June 2015. 57 months Estimated length of time to build if using traditional methods (from start on site ): 6 months longer, 63 months in total Briefly describe the construction method SIP infill to concrete frame. Innovaré provided 162 mm i-SIP panels which could achieve a low 0.19/W/m²K u-value. The sub-structure is a mass fill foundation. Why was this method chosen? i-SIP infill consists of structural insulated panels manufactured offsite and transported to the building site. As the panels are prefabricated, infill does not have to be assembled by hand. Kidwells Estate has constrained access in a number of areas due to low rise buildings in close proximity to each other. This live site also had a number of noise restrictions due to residents remaining on the estate while works were taking place. A high performance infill solution was needed to combat the increasing costs of energy faced by residents. How did costs compare with traditional methods? The Wates project team concluded that the switch to the i-SIP system made a 10 percent overall programme gain and a 25 percent saving of the cost of their mechanical and electrical provision. Significant financial benefits were delivered, as Innovaré did not require scaffolding during their works and also replaced edge protection as they completed each floor by virtue of including a timber barrier to all apertures. Would you use this method again? Yes. What are your reasons? It potentially reduces scaffolding costs. Scaffold periods are reduced by using SIPs. The infill is quick to install and is high performing thermally. It integrates well with pre and follow on trades, removes the risk and hassle from the construction site.

38 Case studies Transforming Construction More Homes Through Manufacture A Housing Forum Working Group Report Case study 10 Olympic Way, London Contributed by Rory Bergin HTA Design LLP rory.bergin@hta.co.uk Name of project: Olympic Way Town or city: Wembley, London Brief description: As one of the tallest modular buildings in London, the Shubette House re-development sits at a prominent junction adjacent to Olympic Way, the main pedestrian route connecting Wembley Station and the stadium. With 158 new homes and a 237 room hotel (with commercial and leisure uses, associated parking, landscaping and play) the project delivers a new mixed use scheme of the highest quality, delivering much needed housing (private, affordable and rent) and amenity provision to the area. The buildings were designed for offsite manufacture using the Vision Modular System - a volumetric solution delivering advantages in speed of construction and reductions in defects while offering the fl exibility to deliver the varied forms and tower that are incorporated in the design. The tenure mix is: 83 percent private, 17 percent affordable, 7.5 percent social rent, 9.5 percent intermediate. Total cost: £44 million Average cost per unit: not supplied Principal partners: Donban Construction (contractor), Network Housing Group, Pinnacle, Novotel, Residor by Radisson HTA Design LLP (architect). Completed: 2013 Length of time to build (from start on site ): January 2011 – November 2012 (onsite for 1.5 years) External delay of 6 months. Estimated length of time to build if using traditional methods (from start on site): 2.5 years

39 Briefl y describe the construction method Volumetric construction, steel frame modules, slip-form concrete for cores, rainscreen cladding, concrete podium over parking. The entire scheme has been designed to be constructed from steel volumetric pods. We believe it to be the tallest volumetric residential tower in Europe. Through volumetric construction the scheme aimed to improve build quality, reduce construction waste and speed up the construction process. The tower balconies were constructed as part of the modules and used as supports for the façade works, removing the need to scaffold the building. Why was this method chosen? The system is the contractor’s preferred construction method. How did costs compare with traditional methods? Similar costs but shorter construction period. Were there any additional/ unusual approvals needed? No. Would you use this method again? Yes, we are working on three more projects with the contractor. What are your reasons? Quality of the build, speed of construction, repeat business. Were there any diffi culties with the method chosen? Design decisions must be made on time to enable the factory to start production of the modules. Stacked structures and services are needed in the design.

40 Case studies Transforming Construction More Homes Through Manufacture A Housing Forum Working Group Report Case study 11 Enfi eld Small Sites, North London Contributed by Iain Stevens Airey Miller Partnership LLP iain@AireyMiller.co.uk Name of project: Enfi eld Small Sites Town or city: Enfi eld, North London Brief description: Seven schemes - Parsonage Lane, Jasper Close, Forty Hill, St George Road, Lavender Hill, Tudor Crescent, Holtwhites Hill - comprising 94 dwellings. Mix of houses and apartments for market rent, social rent and shared ownership. Total cost: Approximately £15m Average cost per unit: £160k Principal partners: London Borough of Enfi eld (client) Kier Project Investment (main contractor), Climate Energy Homes (principal contractor), Airey Miller (project manager / emplyer’s agent), HTA Design LLP(planning architect) BDG Design (executive architect) Length of time to build: 18 months (completion in December 2015) Briefl y describe the construction method Offsite manufacture has been used, in the form of the EcoTech Timber Frame system supplied by Climate Energy Homes, to provide high quality, sustainable housing on time and in budget. All dwellings were constructed to Code for Sustainable Homes Level 4; however, the system lends itself to achieving all code levels, zero carbon and passive houses. Why was this method chosen? The EcoTech system was chosen to achieve high sustainability and quality levels whilst achieving a fast delivery programme to compliment the PRS approach. How did costs compare with traditional methods? Costs were comparable to traditional construction and the EcoTech System provides long-term benefi ts in terms of whole life costs and running costs for energy bills. Would you use this method again? Yes, and the Enfi eld Small Sites project is currently being extended to provide an additional four schemes. What are your reasons? To achieve high quality and swift project delivery and allow the client to use the private rental market income to generate funds for future development in the borough. Were there any diffi culties with the method chosen? There were design challenges with tailoring the traditionally designed scheme approved by planning with the EcoTech system but this is being successfully overcome.

41 Case study 12 Hanham Hall, Gloucestershire Contributed by Paul Newman Kingspan Timber Solutions paul.newman@kingspan.com Name of project: Hanham Hall Town or city: South Gloucestershire Brief description: Range of one to fi ve bedroomed properties: in all, 185 properties. Total cost: not supplied Average cost per unit: not supplied Principal partners: Barratt Development (client), HTA Design LLP (architect), Barratt Homes, Sovereign Housing Association, Kingspan Timber Solutions Length of time to build: About three years Were there any additional/ unusual approvals needed and what were they? Zero carbon development needed to meet demanding requirements of ‘Carbon Challenge’. Briefl y describe the construction method Structural insulated panels (SIPs). In a typical external wall construction, a vapour barrier was stapled to the external face of the Kingspan TEK Building System panels followed by timber cladding fi xed on battens. Then, 25mm-thick Kingspan Insulation Thermawall TW55 was installed internally, helping to further reduce both heat loss and thermal bridging, followed with a service cavity and a layer of plasterboard. This internal build-up was also used for the roofs. Why was this method chosen? High performance characteristics of Kingspan TEK Building System and established track record in assisting projects reach the top standards in building performance. The constructions also achieved outstanding thermal performance, with a typical roof and wall U-value of 0.11 Wm2/K, whilst the Kingspan TEK Building System’s unique jointing system helped maintain air leakage rates below the target maximum of 1.5 m3/m2/hr @50 Pa.

42 Expert Opinion Andy Von Bradsky More Homes Through Manufacture A Housing Forum Working Group Report EXPERT OPINION: THE DIGITAL REVOLUTION ANDY VON BRADSKY ON INTEGRATING DIGITAL TECHNOLOGY AND OFFSITE PREFABRICATION 1 Metek steel frame federated with architectural BIM 2 Design clashes identifi ed prior to construction, reducing risk 3 Architectural model includes and coordinates service intake and slab setting out onstruction in the UK is increasingly using digital technology to speed design and improve effi ciencies and this is beginning to be taken up in modern housing construction. So-called Building Information Modelling (BIM) can be thought of as creating a virtual prototype. It allows any aspect of a design’s performance to be simulated and assessed before it is built – helping to understand the design more completely and much earlier and so reduce expensive risks later in the construction process.. The information generated in this digital model can provide a blueprint for a factory to manufacture components based on the design a process known as design for manufacture and assembly (DfMA). Using DfMA has benefi ts for customers in that they can visualise what the home will look like, and it also makes it easier to customise the design to refl ect consumer choices. The BIM data is stored and can be accessed digitally for whole life management and maintenance regimes. It also benefi ts the contractor because BIM-generated information is transferred to manufacturing software, enabling the production of frame construction drawings in remote factories, which is then used for the direct manufacture of components. Modelling off-site manufactured elements can halve the labour needed when linked to Computer Aided Manufacture operated robotics. BIM was used extensively in the prefabrication of components at the Oval Quarter in Lambeth, where PRP was the architect (see page 29). We worked closely with Metek which manufactured the offsite

43 4 5 Exact coordination between OSM steel frame and opening in external wall to brick dimensions Environmental performance of external building fabric established early in design stage with confi dence using architectural model content as basis for analysis 6 7 Availability of 3D views within construction documentation improves communication of the detail design intent during procurement and construction Using DSfMA has benefi ts for customers in that they can visualise what the home will look like Integrated modelling process and collaborative approach meant team could react quickly to changes steel framed components as shown above. Using BIM the fabricator was able to resolve spatial ‘clashes’ prior to site. The key to success was collaboration and integration of the supply chain team early in the design process. The fi rst two-storey units were built in seven days as it was critical that occupants could move in quickly. Zone specifi c colour-coded sections and BIM coordinated just-in-time delivery made this possible. Offsite manufacture and the digital advancement taking place in the construction industry presents an exciting time for house building, and one that should drive benefi t for consumers too. Andy von Bradsky is Chairman of PRP a member of The Housing Forum

44 Concluding Remarks More Homes Through Manufacture A Housing Forum Working Group Report Concluding remarks Jim Martin, Chair of The Housing Forum’s Working Group, Smarter Supply: Smarter Resources, weighs up the evidence for offsite manufacture in housebuilding. This report demonstrates that the case for Jim Martin Chair of the Housing Forum’s Working Group, Smarter Supply: Smarter Resources offsite manufacture (OSM) is compelling. As we’ve seen from the case studies, prefabricating homes in factory conditions delivers numerous advantages. — Higher quality of building, being assembled in controlled, benign conditions, from standardising process and factory testing. — Greater certainty of programme because of simplifi ed site processes and works becoming less weather dependent. — Improved energy performance through enhanced specifi cation and controlled, factory processes which allows much more accurate jointing and testing of components, to reduce air leakage, increase insulation and seal airtight components. — Safer working conditions. Working in a controlled environment can reduce accidents and improves safety. The use of pre-assembled components has been increasing in many sectors of the construction industry over the years and it is almost impossible to build anything without a high proportion of preassembled components within the structure. New commercial buildings, hotels, education buildings and health service buildings are all exhibiting a very high proportion of OSM as standard: curtain walling, services pods, and classroom extensions. Existing companies such as Laing O’Rourke are making major investments in the OSM process. The cost of OSM is coming down because there is now a steady fl ow of work into the manufacturing facilities at volumes that make the process viable. As production runs increase with volume, the comparative cost should reduce. It is

45 also possible to locate the manufacturing facilities in lower economies, which improves regional development and reduce overall labour costs. OSM will reduce preliminaries costs by shortening project duration. OSM can offer the standardisation required for the economies of scale but now OSM can also offer increased flexibility and customisation by the use of computer modelling, BIM and greater customer engagement – in the same way the car industry does. Because the OSM product is much more predictable in its construction and performance, it will allow much more accurate Home Performance Labelling. This will give purchasers a much greater level of energy and running cost information when they buy a new property. Long term cost reduction can be achieved through OSM. Labour is always a very significant component part of the overall cost of a building. OSM factory-based work can achieve three times the productivity of site labour, thereby potentially reducing the labour cost. Strangely, it is the residential sector that has been the slowest to embrace OSM, but this is likely to change. If we, as a nation, are to build the numbers of homes we need over the next 20 years, we will need to use every means available. The combined residential development industry currently has a capacity of about 140,000 homes per year. We need to develop 200,000 homes per year, as a minimum, and we will need the additional homes that can be developed using OSM in order to make up that shortfall. There will be hurdles, challenges and problems Mar City Homes specialises in modular construction to build homes shown in these phorographs to solve ahead but unless we in the residential development industry begin to embrace OMS we will not move forward significantly on the quality of our product, we will not move forward significantly in terms of energy performance and perhaps most importantly, we will fall short of the national target for homes.

46 Credits More Homes Through Manufacture A Housing Forum Working Group Report Credits The Housing Forum is indebted to the many people who contributed to the content, writing and production of this publication. Working Group Chair: Jim Martin, Senior Partner, Martin Arnold Editor and production: Denise Chevin Design: Mark Bergin Contributors and commentators: Rory Bergin, Partner, Sustainable Futures, HTA Design LLP, Andy Von Bradsky Chairman PRP, Stewart Hackney, Business Development Manager, Fusion Building Systems, James Lidgate, Head of Residential, Legal & General, Graham Perrior, Head of Standards and Technical NHBC, Terry Mundy UK Business Development Manager, Lloyds Register EMEA (for BOPAS ), Peabody, Orbit and Accord and Mar City With thanks to: all case study contributors and special thanks for resident case studies to Natasha Devlin, Peter Webb, Neil Crowther. Interviews by Stuart Macdonald, See-Media, Photography by Ed Tyler. This report has been developed by our Smarter Supply: Smarter Resources Working Group members: Tim Attwood, Director, Conisbee Steve Bannister, Procurement Manager, Wates Living Space Euan Barr, Head of New Business, Watford Community Housing Trust Richard Barwick, Interim Construction Project Manager, The Hyde Group Tony Battle, Joint Managing Director, Kind & Co Rory Bergin, Partner, Sustainable Futures, HTA Design LLP Sally Binns, Commercial Product Manager, Marshalls Graham Brown, Director (Bouygues UK) and Board Member South East LEP, Bouygues UK Housing Rick Burgess, Partner - Technical & BIM, PRP Bobby Chakravarthy, Associate Partner, Arcus Andrew Cleaver, Regional Development Manager, AkzoNobel Steve Coleman, Director, Takeparts Garfield Coombs, Business Unit Director – Homes, Osborne William Cornall, Director of Development & Assets, asra Darren Eccleston, Pre-Construction Director, Wates Living Space Leona Eze , Graduate Building Surveyor, Martin Arnold ( with thanks for case study support) Cody Gaynor, Managing Director, Space Craft Architects Stewart Hackney, Business Development Manager, Fusion Building Systems Adrian Heys, Head of Development , Town and Country Housing Association Roger Holdsworth, Partner, Pollard Thomas Edwards Architects Karen Jones, UK Housing Building Manager, Kingspan Insulation Steve Kane, Deputy Managing Director, Hill Charlie Lacy-Scott, Senior Sales & Marketing Manager, Willmott Dixon Gary Lawrence, Senior Project Manager, Silver Simon Major, Commercial Projects Manager , AkzoNobel Alistair McLeod, Director, Waterstons James McMillan, Assistant Development Director, Great Places Jon Milburn, Development Director, Guinness South Paul Murtagh, Director of Property, North Hertfordshire Homes Alex O’Keeffe, Project Manager, Home Group Sandy Pahl, Construction Project Manager, The Hyde Group Dave Poulter, Partnership Housing Projects Director, Wates Living Space

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