The Future of Housing in Wales?
Housing providers are showing significant interest in commissioning more of the all-Welsh-timber homes built by Ceredigion-based solar homes project Ty Solar, the company says, following the letting of their first homes for social rent.
While housing providers were initially sceptical about the all-timber design, since the first houses have been completed and let, chief executive Glen Peters reports the firm has been “deluged with enquiries”. Some are being followed up with serious discussions that look likely to result in orders for more homes, he says.
The timber-framed, timber-clad, highly-insulated design of the homes is intended to create dwellings that are inexpensive, healthy and low-carbon – both to construct and to occupy, thereby meeting local housing need and helping people at risk of fuel poverty.
The first Ty Solar home was built as a prototype at the company’s base near Cilgerran. The prototype three-bedroom home saw fuel bills of just £ 200-£300 per year. At that stage however it proved hard to interest traditional housing providers in an all-timber home: “We would have been happy to build our next units and hand them straight over to a social landlord, but none were interested. So we decided to go ahead and build our own. The legislation had changed, so we were able to become a private social landlord, and that’s what we did.” Six homes have now been built at Glanrhyd, a tiny village not far from Cardigan, and the first tenants have moved in.
Timber inside and out
Peters says that local wood was chosen for the construction primarily because timber is an inexpensive building material. “It is also a low carbon material and available locally, offering very low carbon footprint for transport as well.”
The homes aim to support the Welsh construction supply chain, with a target of 80% of the capital spend from Welsh suppliers. “Coed Cymru were very helpful with sourcing our timber. We asked them to find sources of sustainably managed local timber, and they did the research for us.”
“Locally, a substantial quantity of larch was being felled because it has blight – this was being burned in a power station, which seems a terrible waste when it could be used as a building material, and the carbon sequestered.” Ty Solar secured a licence to use and process local larch, which they sourced the National Park’s Cilrhedyn sawmill in the Gwaun valley, just a few miles from the site. “There were no quality issues with the wood, Peters adds, “we trained one of the team to pick timber and our ‘rejects’ pile at the end was very small.”
The high-performance triple-glazed windows were made locally from Douglas fir, also sourced from the Gwaun Valley; the structural frames are of softwood, mainly sitka spruce, supplied by BSW sawmill at Newbridge. The homes are insulated with almost 300mm of recycled newspaper, produced by Welsh firm Pen-y-Coed.
As well as allowing for lower-impact construction, Peters also believes that timber is more flexible and less problematic at the building’s end of life than traditional heavy construction materials.
“As well as being high-carbon, brick and concrete buildings are permanent and indestructible. Yet everything is changing so fast; jobs move in less than 50 or 60 years. With masonry, you build in permanency, yet in less than 50 years huge brick and cement buildings are having to be pulled down, which is expensive and disruptive, or they have to be repurposed, which is again very expensive. Timber is a lot easier to deal with – and the material can much more readily be re-used or recycled.”
Structure and design
Another design priority for the team at Ty Solar was occupant health. “We wanted a structure that was breathable, and we also wanted to minimise the use of chemicals. There are no construction material standards in the UK comparable to those, say, in Germany, but we are aware there are issues with some chemicals used in building products potentially linked to breathing problems – and we did not want to use any carcinogens. We also avoided conventional paints, which can have high volatile organic emissions, and used earth paints instead.
“We developed our own construction method partly because we did not want to use SIPs (structural insulated panels) so we could avoid polyurethane foams.”
To keep things simple, the structure is based around the standard 14’ lengths supplied by the sawmill. Open frames are assembled in Ty Solar’s factory – a converted former cowshed. “About 40% of the construction takes place in the factory, taking one to two weeks, then the frames are transported to site where the house is erected in around three of four days. It is then shrouded in membrane and made weathertight, so work can start inside. Windows can either be installed in the factory – which does increase the risk of breakage – or on site.”
The detail of the six homes at Glanrhyd has been simplified from the original prototype – a slightly different structural approach has been developed for the new homes, with panels rather than box beams, and a concrete block and beam floor rather than timber. “Although we originally used a timber floor, this proved a lot more complicated and expensive, partly because of the need to include rodent protection, and partly because it had to be elevated, which then necessitated an access ramp”.
The shape of the homes also helps both to keep construction costs down, and energy performance up.
A simple form, with no awkward dormers or set-backs, greatly reduces the surface area in relation to the volume, minimising heat loss. A simpler form is also usually a lot simpler to construct – and to construct well.
Instead of employing a complicated shape, the visual appeal of the houses lies in the texture of the wood cladding and the two runs of shading, above the ground floor glazing and again at roof level. The shading serves both to protect the cladding (and occupants) from the rain, and to minimise overheating from high summer sun, while allowing the lower winter sun in to warm the interior.
In order to leave the larch untreated, in line with the ‘no carcinogens’ approach, care had to be taken with the design. “We spoke to Dr Ivor Davies at Napier University in Edinburgh – he has written the British standard for cladding, and is extremely knowledgable,” Peters says. “He was able to direct us to ensure the cladding has a full drying season every year – hence the overhangs to protect the cladding from rain. It can be left to weather naturally with no additional treatments. ”
As social homes, the rent is fixed externally, set at 80% of the local market rate. Ty Solar’s build cost of around £1,300/m2 is comparable with other social homes, and the feed-in tariff revenue from the large 6kW array of solar panels on each house is retained by Ty Solar (the occupants get the free electricity) which helped subsidise the rents. (Now the government has “slashed and burned” the size of the feed-in tariff, the sums will be made up in a different way, Peters adds)
The homes were offered to households on the local housing list. Ty Solar were able to choose their tenants: “They needed to sign up to the idea that the planet is important, timber is important, that they have to look after the houses, and can’t just put holes anywhere on the walls.” They had no problems tenanting the homes: “It mainly appealed to younger people: those who were in real housing need were bowled over by the houses, and gagging to get in.”
“We became a landlord incidentally, but it has turned out to be really useful: housing is not just about the design and technology, we are also learning about how people live in their homes, about the living experience.”
Acceptance and wider interest
When the first tenants moved in near the turn of the year, publicity in the local and national media led to renewed interest in their housing model, Peters says.
“Although we couldn’t get anyone interested when we proposed these homes two years ago, there is a lot more interest now – we have been deluged with enquiries. Although a lot are probably driven mainly by curiosity, some are more serious, and we have entered into negotiations with a couple of providers and are hoping to make an announcement soon.”
Peters suspects that possibly one of the factors opening up the interest is the fact that local authorities are getting back into housing provision, after much social housing was transferred to housing associations in the 90s and 00s. “Many of the property people in the housing associations are from a traditional ‘bricks and mortar’ background. They believe a house has to be clad in brick and have PVC windows, and have been a bit suspicious of timber building. Perhaps the new local authority teams are coming to this fresh.”
Peters feels that it is not just the construction of the homes that is unique, it is the fact that Ty Solar are looking at the longer-term benefit the homes can offer. “One thing we really would like providers to start thinking about is the full life-cycle costs and benefits of their buildings. We have made our decisions based on the life-cycle benefits to occupants over 25 years. For example, we estimate that the free solar electricity offers around £1k benefit each year adding up to £25,000 over 25 years. Then we looked at transport – in this area you more or less have to run a second car, as services are so dispersed and public transport so poor. So we have offered use of a free shared electric car; we estimate this is equivalent to a benefit of another £1,000 per year in saved running costs. If you add these benefits up over 25 years, it represents a return on the investment around four times the capital cost. Yet the average RSL just looks in terms of build cost per square foot rather than taking a life cycle approach.”
Interestingly recent research shows that homes which are energy efficient, and therefore likely to be warmer, healthier and cheaper to run, may offer better financial returns to landlords, as well as meeting more of their social obligations and sustainability targets.
Research was carried out by the charity Sustainable Homes into the relative financial performance of social housing units in relation to their energy efficiency rating. As homes were ranked as more energy efficient, they turned out to be void for a shorter length of time – on average, 31% shorter for efficient band B properties compared to those in bands E and F.
Landlords with more energy efficient stock spent less on refurbishing void homes, less on repairs and less on staff time to manage voids, and less time and money on chasing rent arrears, which were on average two weeks higher in Band F properties than in more efficient homes. This bodes well for any landlord who, like Ty Solar, is looking to reduce costs for their tenants.
Kate de Selincourt March 2017