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sustainable placemaking forum 79 Parkway London NW1 7PP tel. 020 7485 8555 fax 020 7485 1232 |
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seminar proceedings |
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A seminar series organised by HTA Architects Ltd Report of seminar held on new technology (centring on lightweight steel frame systems) held on 12 September 2000 in London Main conclusions More and more developers are showing interest in using prefabricated systems and building processes - gaining market advantage is an important reason Insurers are positive about prefabrication because more than 90% of current claims result from poor workmanship: these can be eliminated or substantially reduced with factory working Systems must not be seen as purely for the public sector to avoid stigmatisation: one steel producer believes that it is vital to develop private market acceptability first Design has a major role to play in ensuring that standardisation of products does not lead to drab uniformity A major problem for innovative new building systems is perception following the failures of the 1960s and 1970s systems. But there is evidence that customers are being persuaded by the benefits To achieve viability, manufacturers need volume, though with the move to 'just-in-time' systems linked to sound partnering arrangements, those volumes may amount to as few as 250 homes The Housing Corporation's 'kickstart' special allocation for innovation is a welcome initiative Steel frame manufacturers and developers believe this is a more sustainable product than wood, for which there are only limited numbers of sustainable sources Jim Baker is an American Architect and chief executive of Forge Llewellyn, which is dedicated to the development of cost effective, factory implemented environmentally sound housing. He has experience in the development of building systems over three decades in the UK and the US. These include concrete, timber frame and steel frame. He is on the BRE steering committee for advanced off-site production of steel and timber building systems. Forge Llewellyn is jointly owned by Walter Llewellyn and the Forge Co (UK). Lessons from the past - and present The Forge company has timber frame buildings that were prefabricated more than 150 years ago. In the New England winters you had to prepare, so that in the spring time you could build quickly - the basic structure could be put up in less than a week. One building - the Forge - was totally prefabricated in 1840. Each piece of timber was marked to show where it fitted into another piece. I took it over 25 years ago. Despite not being used for 50 years we were able to repair it. It was truly sustainable: it has everything to do with what we are doing today. We can also learn from the aircraft and motor industries. Designed in the 1930s, the DC3 (the 'Dakota') provides one the best examples of good design in aircraft. It revolutionised the industry. It was comfortable, reliable, affordable, durable and also very safe: you can still fly these planes. It's a sort of 'vernacular' aircraft. Today in the car industry we have the Ford Focus. I believe it is the greatest car on the market. It is most affordable with top performance; it's lightweight, materials are recyclable and re-usable; it's environmental to the extent that any car is. This is the best car I have ever driven. It provides choice - not infinite choice, but a narrow, acceptable choice. However, by contrast, contemporary houses are too small and very expensive. I believe there are opportunities all over the place for a new vernacular: we are looking for the 'ford' in affordable. Forge Llewellyn approach The elements we are dealing with start with the structure - the foundations, walls and frames. We are aiming for a highly insulated tight envelope - walls, windows, doors and roofs. After getting the envelope right, we turn to services. We have got our heating system costs down to a mere £25 a year. We haven't tackled that hot water yet. We are interested in using recycled materials and those that can eventually be recycled, and that are environmental. Forge Llewellyn is concerned with a kit of parts that you can put together. Some years ago we were employed to design houses that could be built in Bahrain from kits of parts. We came up with about 20 parts that you could combine in all sorts of different ways. An indigent Bahrainy could buy it in the local do-it-yourself store, and construct it to one of 1001 designs. The importance of design This is all about design - I am not talking about style - which drives the solution. It is about the fundamental business of putting things together, whether it is a screw going into a piece of steel or the entire envelope of the building. Viability Commercial and affordable - these two different concepts have to be balanced. We are talking about housing that is affordable to the user both in first cost and the long costs. The corollary of that is that it must be commercially viable. There is an example of how not to do it from a Swedish company, which went to the United States in the 1980s. They knew a lot about timber frame houses and decided to set up a vertically integrated factory and placed it close to a good road network. But they forgot one thing - the market. They expected everybody to come to them because they were able to build timber frame houses economically - but they were commercially unviable. Eventually the factory closed and the equipment scrapped. Why steel We do not sell steel - we use it. We think it is the best material out there today. I have built with a big range of materials and I am totally convinced about steel because it is affordable. The capacity of rolling mills far exceeds the amount being used. It is high performance. We can create the best acoustic systems available on the market today, with good insulation and fire protection. It is environmentally sustainable. People often say wood is more sustainable but that is wrong. Huge areas of the world have been deforested: there are only a handful of forests that are being harvested sustainably. Often using wood means destroying an environment - both human and natural. I have nothing against timber frame but you have to select it carefully and know what you are doing. The rain forest alliance wants us to cut use of timber by 75% - in the US paper and housing are the biggest users. Steel is sustainable and whole life costing analysis shows that it is flexible, predictable and bug free. It is also very flexible - if you don't like one piece of steel you can get another. The process Most of the steel we use is cold rolled - three tons is enough for one house. After rolling, it is made into large panels. We are now combining hot rolled steel with cold rolled, and combining volumetric elements with panel elements. We use as few parts as possible. Making a building is about joints - the conjunction of all the materials. As architects we spend the time not in the middle of the panel but where one panel meets another, or a door or window. So if we have just 24 panels we have just 24 joints. We are now looking at three dimensional approaches which are more complicated. We built estate offices for Hanover Housing. The unit arrived at 8 am, by 10 am the crane had gone and the tilers were working on the roof and by the end of the day the key was handed to the estate manager. That is terrific but you can't use it all the time - there are horses for courses. There is a real question of mix and match; it isn't all modular or all panels. Part L You can't fool mother nature. Steel, for all its benefits, it has one big problem - it conducts heat 4000 times faster than wood. If you solve the problem of cold bridging you get marvellous houses. We put all the insulation on the outside so that you get a warm frame and a very warm house. We put a very special render on the top which seals it up - it really works. You can use bricks, timber or other finishes, but in these cases you need to put more insulation behind them. We are very interested in service systems. Our houses have only a 2kw heating load compared with the average of 10kw. Similarly, our average air change amounts to less than 2 cu metres an hour compared with the UK average of 10 cu metres. This means good and bad news: you have a ventilation problem. We have been working with Baxi on prototype heat recovery systems which are not there yet but are going in the right direction and capture 90-95% of the heating generated in the house. Technically speaking you could heat one of these houses with a light bulb. The system has another benefit: it takes pathogens out of the air. Two children who previously suffered from asthma have not had attacks since they moved into the house. We are also looking towards the sun - the trouble is you do need a lot of it. The clue is to insulate the house. To adapt the old saw: it's about insulation, insulation, insulation. Partnering in the supply chain We could have got where we are without the help of lots of people - including Llewellyn, Berkeley Partnership, Baxi, Lafarge and Rockwool. We have been working with most of them for ten years. The relationships we have involve open covenants: we don't have hard and fast deals with everybody but we do have trust. If Lafarge does tests for us and develops a fire proofing system, we use them. To use someone else would break that trust. When we have a partnering relationship it is not very complicated, generally an exchange of letters. It is staggering the amount of money these organisations have put into R & D, in addition to our own funds, to support our operation. One thing you need for advanced technology is money. When we set up Forge Llewellyn we set it up as a not-for-profit ethical investment because the people who invested in it believed in what we were doing. It was a very important concept but eventually had to be sustainable - it was hard road to begin with, and expensive. The future So where are we now and where are we going? We think we have the basic elements in hand. What we need is repetition much like car manufacturing. You can't simply do five houses here and 16 houses there. It doesn't work We need more design input, manufacturing support, and a lot of patience, continuing enthusiasm and practice - that means clients: if we don't have clients we can't practice. I believe steel is a primary element as a means of achieving the DC3 or the Ford Focus of housing. I think it is a great material. Discussion Perceptions, stigmatisation and commercial acceptance Developers are aware of perceptions about prefabricated systems, because of the history of problems in the 1970s and 1980s. The public fear they might get short changed, while housing departments fear systems will be foistered onto tenants. They are concerned that prefabrication could prove unpopular and disastrous and they could be held responsible. Observer There is a fear of the unknown in the UK above anywhere else because of the specific problems. But it does also exist in the United States. In the 1980s I was involved in building timber frame houses in Princeton, New Jersey. Estate agents were concerned that producing/ homes in a factory would kill the market. They agreed to an experiment with the first one but it had to be brought in under cover of darkness. By the time we had full daylight most of the frame was up and nobody knew what hit them. I don't think there is a real problem with the consumer - rather the problem is with the developer who is afraid of the consumer. Most people if asked how a house had been built, have no idea. Do I know what the Ford Focus is made of? I think it is the perception not the reality. It is a question of struggle and maintaining enthusiasm. You don't win on day one - you have to carry on. Most of our work in the US is commercially based. We have never had any problem selling steel houses - people tend to say they would rather have one of those - we can sell them faster than timber frame houses. Most of our work here is with housing associations because we can give them a product that costs less to operate, is more comfortable for the tenant and has fewer defects. We have not had anybody in post construction interviews say they don't like the house - they don't know it's made from steel. Jim Baker We are also embarking on steel frame modular housing. We have looked at lists of the pros and cons. There is a long list of 'fors' . There is only one 'against' and it is perception. There is nothing else, but it is a huge issue. It is a big risk for people when they don't have to buy it. They need to be convinced that they are getting a much better product. But that is going to take a while. In the end, hopefully, there will be a premium for this type of product. We should be mindful that innovation does not become stigmatised as only suitable for tenants. Developer/housebuilder From a marketing policy point of view, avoiding stigmatism of system building is fundamental to our plan. In our case the private sector came first - technology and products had to be purchased and lived in on private developments before anyone would start to work with the social housing sector. We have been involved with producing some extremely expensive houses - costing in excess of £1 million each - built using simple steel frame. There is no potential for stigmatisation there - it is all about quality. Manufacturer/supplier I have been involved in promoting and developing the lightweight steel frame approach to construction generally for ten years as a major project by British Steel. We are very aware that you ignore the public perception at your peril. But I have been most encouraged by the surveys carried out periodically particularly with those who have lived in steel frame houses. 20 families who had lived in them over two winters were surveyed: all said they would seek out another steel frame house. We take that with a pinch of salt because like most other people position, size, affordability and so on will take precedence. Tens of thousand people visited a steel frame house several years ago at the Ebbw Vale Garden Festival and they were positive. I think when you give people the opportunity of good quality which maybe costs a little more, they are quite likely to go for it. But it is a big step for a developer to change substantially. I am impressed by how developers have taken on innovation. They can, after all, make their money by building more or less what they currently do. The situation is not something we should blame the developers for. It is a natural result of the structure of the housing market in the UK: in other parts of the Continent there is much greater flexibility, because the structure of land purchase and availability is completely different. That is very important. The issue is: how do we create an incentive for developers to put much better quality, variety and interesting housing in place so that the public do have real choice of style, quality and flexible open space? How something is built is really not an issue - it's what is actually delivered. Manufacturer/supplier We have looked at six to nine storey steel frame structures rather than concrete, and using steel panels. In urban areas in London and the south east that looks very good: costs are on a par. Timber frame is becoming more acceptable. But many customers such as housing associations still want to know a lot more detail. Many want the trustees to visit the plant to see what is being produced. For our purchasers, design and location are key criteria, rather than affordability. Mortgages are not an issue - timber frame is acceptable. Developer/housebuilder Practical experience There is no doubt that all developers are trying to find ways of providing a better product, one that is more consistent and what the customers want. We are experimenting with modular systems. We face real problem finding the trades to finish off, particular in the south. With modular, you are working in a factory with a multi-disciplined labour force. It is 90% completed in the factory and comes to site requiring a week to finish. We are building the whole house in four sections - including the kitchen and the bathroom. It is delivered by lorry with the roof finished, external brickwork in place, painted and carpets down if you want. It's a 'zip it up' form of technology. Our experimental homes are in the middle of nowhere, and when people see them, they wonder why we have dragged them out just to see a couple of houses. That is what we want to hear them say! There are other savings and benefits from environmental impact. There are no fork lifts, no scaffolding, no compound, and no other lorries. You have no waste on the site. For the local environment the benefits are amazing. And you don't get kitchen worktops delivered 150mm too long, which have to be cut down on site. We are working to 2mm tolerance, something unheard of in this industry. We get consistent quality, tested in the factory. But there is a long way to go. We believe that defects and snagging and defects will be reduced dramatically. If you find a problem keeps coming back you go back to the factory to resolve it - you can control it. On site you have no idea which chippy is at fault. Factory completion allows you to test everything and should substantially reduce defects even if not to zero. You can also achieve fixed completion dates. You are not affected by the weather. You can't at the moment get innovation cheaper. The Housing Corporation has realised this and introduced its kick-start allocation for pre-fabrication. Every manufacturer, whether it's steel or timber frame, will only get the price down if they know they can get the quantity coming through. We are working with NHBC and Zurich: they are ecstatic about it because they see their risk being minimised - 95% of the claims they meet have nothing to do with materials. It is all about workmanship. Developer/housebuilder Essentially most housebuilders build houses for stock. The big change will be in making things to order, which is something you can do with systems. I once worked for a company producing worktops and cubicle systems. We changed to a made-to-order operation. It completely changed the structure of the company. But with housebuilding the key changes are not just in technology but the commercial relationships and the supply chain. Those 'soft' issues - including planning which is just one of them - are far more difficult than the technical issues. Until everybody in the participating organisations buys in and understands, you will not get the benefit from these systems. It is fundamentally different. Trying simply to bolt on new ideas will be like a Trabant with an aerofoil on the back - it won't go any faster and won't work. To make a 'just in time' system work everybody must sign up to it. Otherwise they will have a little stockpile on site because they 'know' the delivery will not arrive - that is not the way to do it. Manufacturer/supplier Funding and insurance Housing associations are concerned about sustainable investment. Although it is not the case with timber, steel frame and some of the modular systems still haven't been accepted by lenders - they do not seem to be up to scratch with the market. We need to do something of a selling job. Some of the shared ownership associations and their buyers have faced problems. Housing association My experience is that it is not an issue. Those investigating steel frame have been satisfied that they can get funding and insurance cover. In parts of the world innovation is reducing premiums. Improving profit margins is more likely in this country but it could lead others into competition. Manufacturer/supplier When we took funders to see our scheme we explained that the products were coming with 60 year agreement certificates as were the parts coming with it. Corus suggests the steel should last 1000 years. We were then asked us what happens in year 61! At present houses come with a 10 year NHBC certificate and people accept it, yet they question 60 years. I am not sure how you overcome that. Developer/housebuilder Effectively our product has got to be maintainable for ever, because that is what people really want from their houses - that is where the 1,000 years come from. It will last, so long as you maintain the external envelope, which is really the same as for any other type of house. Manufacturer/supplier Planning issues Planning is a serious problem. We have two sites in the south east. We started the factory up in anticipation of getting planning permission. But the committee decided to defer a decision yet again. It was nothing to do with planning but whether they wanted 'experimental houses'. Effectively the committee refused to vote. We had to turn the factory off. In this country we can control every aspect of the business but planning. If the government wants this to work, it has to resolve planning. It could be the downfall of this type of construction. Developer/housebuilder Creating volume . I am hugely heartened to hear from developers that they can deliver improved performance, reduced cost increased quality and reduce time on site. But the issue for me is how to get the volume to break through the cost barrier. We need to find a critical mass of clients, suppliers and constructors to avoid turning off factories at the whim of planners. Ben Derbyshire, HTA Architects This could be where this grinds to a halt. Developers are only going to start moving forward on a small scale. They are not going to switch over in a short time to a new system; they will want to see how the market responds and to see if they really do get a better quality product. Developer/housebuilder Manufacturing industry has gone away from large runs of a standard product towards agile production where you can assemble components in different ways to give customised products. If we are not careful with system build we will go down the road of identikit mass production. We have got to put the components together in different ways. We are talking with one developer and looking at between 200 and 500 homes a year. But because that will be a very tight partnership that will be great. It is because we have got the relationship. I don't see that you need to make thousands of houses. Manufacturer/supplier At the moment, steel frame is limited though it may be different in five years time. The technology is out there and there is plenty of steel, but the factories and the trained labour are not available. There are not yet the people making the investment that needs to be made - hence the Housing Corporation's pump priming. If we don't get that investment, then I think you will see the Japanese and others coming in. I think the situation will be transformed. 10 years ago you would buy a car and expect it to break down - you don't now. The whole industry and customer perception has changed. I think the same thing will happen in our industry. Developer/housebuilder We should be grateful to this government towards innovation. At least it is putting in some money and is trying to drive things. The DETR has been very positive in attempting to inflict change on what is a resistant industry. That is very encouraging. There are individuals driving the industry in a competitive way, but not pushing one system or technology. For the first time in my career I perceive a real desire and will to so something to stimulate it. The kick-start programme is a very good example of that. Manufacturer/supplier All our schemes are in partnership with developers: the only way we can access land is through S106 agreements. But will zero defects be enough of an incentive for developers to invest enough time and money to get a product right? I feel it is not, because the customer wants buy something that looks pretty and in the right location, and not because they know it will last 60 years and remain maintenance free - they are likely to move on in three or four years. The social housing market is different. So we need to find common ground. What is in it for you? Housing association I think zero defects is just part of the equation. Building houses on site produces a lot of grief. Providing the customer with a better product should help avoid that. If customers have a good experience of moving in they are likely to want another one from us. If we could get 60% of sales from existing customers it would be fantastic. Manufacturer/supplier There is a very diverse range of solutions from fully modular through panel systems through to traditional (which is not going to go away). The issue is about interfaces - not just reducing the number of joints, the physical details - but in the supply chain. Every time you reduce the list you reduce the necessity for people to charge a profit. If the supply chain hadn't been changed between the Escort and Ford Focus they would not have been able to build it. Until the supply chain is sorted and long term relationships built, you won't get houses cheaper. Manufacturer/supplier How do we drive this forward working with social housing clients? As architects how can we work out a way of predetermining the linkages between products which would be acceptable? If this means that we become part of the supply chain and for instance then always use certain types of windows and components - how do we sell that concept to you? There need to be parts which you have choice about and parts that are predetermined. Peter Lusby Taylor, HTA Architects Other issues We are building for a private housebuilder in Bristol. Although steel frame was not the lowest cost, it worked financially because of the other benefits. It was faster. For instance, wastage is reduced, and less scaffolding is needed. It can be done but my somewhat cynical view is that if a quantity surveyor is costing it we are dead. However, if a project manager is in charge and knows that time is money we are OK. Manufacturer/supplier We are working on Aylesbury and Elephant and Castle with MACE, the project managers. Their observation is that in procuring those projects, traditional construction industry would be incapable of delivering without hugely increased costs and massive disruption to the local population. Ben Derbyshire, HTA Architects We are looking at rolling programmes for the Aylesbury Estate. We took residents to Peabody's modular Murray Grove scheme. They were very interested: it is not exactly want they wanted but they liked the process and the way it was developed. Another point relates to sound insulation. Previous concrete systems were poor on sound. I was very comforted to hear that new systems are achieving very good standards. It will also be important at Elephant and Castle where there will be a huge volume of development on a very constructed site over five years. Ian Jolly, HTA Architects This seminar series operates on a 'Chatham House rules' basis. However, many of the participants have already expressed their willingness to have their contributions credited to them. In the other cases, speakers have not yet given clearance - no inference should be drawn from this. Anyone wishing to quote the speakers should speak to them direct for their permission. For further information, contact Chris Bazlinton, Editor on 01279 771468. HTA Architects Limited 79 Parkway London NW1 7PP telephone 020 7485 8555 fax 020 7485 1232 email hta@hta-arch.co.uk ISDN 0207267 0061
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