Anybody who has sat frozen in a prefab building in their school yard might think the term is a bit of a dirty word. Synonymous with rickety, draughty stopgaps, they are not the sort of places you normally want to spend much time in, let alone live in.
However, an increasing number of self-builders, looking for high levels of craftsmanship, are opting for prefabricated buildings. Indeed, there are many companies in Ireland now creating traditional post-and-beam timber homes with kit-house technology.
“I grew up in a wooden house in America, so when I decided to build in Ireland I started looking into timber frames,” says Joan Dalton, a self-builder from Co Waterford.
“As we started looking into it, it became apparent that it was going to be difficult to find craftsmen in Ireland that could create the handmade home I wanted. Plus, I was looking at how to get a post-and-beam house built in the traditional way, but to do it more efficiently.”
Dalton was surprised to find that everything she was looking for could be supplied by a kit-house company. And she’s not alone — as the market increases, so does the choice.
Most companies building prefab houses in Ireland use post-and-beam structures, but the style of house available can be either glazed or closed-wall.
Prefabricated glazed homes
Stylish, airy and bright, glazed houses take between three and four months to complete to turnkey specification. One of the leading European companies in this area, Huf Haus, has been building in Ireland for a year and was featured on Channel 4’s Grand Design series last year.
“We’re a firm of architects and builders and we provide a full turnkey package,” says Afra Bindewald, a Huf Haus marketing executive. “All that the client has to do is supply the plot of land.”
Along with a thorough design and premanufacturing process, Huf Haus also looks after planning permission and foundations. For a house measuring between 2,000 sq ft and 6,000 sq ft, assembly of a watertight structure on site takes one week. After that, the internals take between 12 and 14 weeks.
“We don’t call them kit houses,” says Bindewald. “They’re pre-manufactured bespoke houses. They’re not off the shelf and each is an individual project. But our signature is the post-and-beam structure — you’ll always recognise a Huf house.”
At €230 per sq ft (or €230,000 for a 1,000-sq-ft home), Huf Haus is at the high end of the market. Nevertheless, this was no obstacle to Nazareth House Management, a company that recently commissioned Huf Haus to build a 55,000-sq-ft care unit for elderly people in Sligo.
“We wanted an innovative design that was bright and uplifting and would assist in convalescence,” says John Hanley, project manager for Nazareth. “We were keen for it to be environmentally friendly with low running costs — care units are usually warmer than most buildings, so to be cost-effective in this area was important. But essentially we didn’t want it to look like a nursing home.”
One of the first health buildings in Ireland to use geothermal heating, the Nazareth care unit is a pioneer in more ways than one — the assembly of the watertight structure, once the foundations were laid, took a mere four weeks.
“From a health and safety point of view it’s a much better way to build,” says Hanley. “People aren’t exposed on scaffolding for months and months.”
Along with speedy construction, another advantage of a prefab over a conventional build is that there is no sawing or patching together on site — the panels can be laser cut in the factory. The preliminary work also means there is less chance of draughts or leaks.
Another company that specialises in prefabricated glazed homes is Davinci, based in Co Waterford.
“We don’t use trunks for the posts, but laminate,” says Volkhard Friese, the marketing and sales manager. “That means it never warps. There are no leaks or unexpected drafts, which is very important in a wet and windy climate — you can lose 70% of energy through that.”
It takes four months to build a turnkey house with Davinci, but clients have to organise their own foundations.
The cost, which includes Philippe Starck fittings, is about €185 per sq ft (€185,000 for 1,000 sq ft).
The design of the houses makes for huge savings in heating. “Our houses cost about €350 per year to heat,” says Friese. Instead of using argon gas in the windows, Davinci uses the heavier crypton gas — the effect, according to Friese, is the same as having a 3ft brick wall.
While the glass is built to keep heat in, the houses are also designed to get the most out of passive solar heating. Each Davinci design takes into account the position of the sun in relation to the site. The overhanging roof, meanwhile, prevents a greenhouse effect when the sun is high during the summer.
Prefabricated closed-wall home
A kit house doesn’t necessarily mean they will be identical to all the others. Closed-wall homes can have different types of cladding on the exterior — stone, brick and timber are all popular. The traditional walled houses are also ideal for those who don’t fancy the exposure of glazing.
Heritage Timber Frame Ltd, an Irish offshoot of Potton, specialises in old English-style architecture. Based in Dublin and Kildare, the homes take two weeks to assemble on site. After that, it takes four to five months to complete. However, Mark Brady of Heritage is dubious about some companies’ promises to provide turnkey finishes.
“We can provide turnkey, but it depends,” he says. “It’s very hard to say you can do it unless you’re based in the area. Otherwise you’re just talking about subcontracting.”
Heritage subcontracts the foundations themselves, and the cost varies according to the exterior finish and the type of heating the client chooses. For a brick finish, it can cost €110 per sq ft, while stone will cost €114 per sq ft (€110,000-€114,000 for a 1,000-sq-ft home).
“The benefits of the timber-frame prefab is the speed of construction,” says Brady. “Within a fortnight you have a watertight house, and after that the tradesmen can all work simultaneously. With concrete, you have a situation where one tradesman is waiting for the other to finish before they can start. And the heat retention is fantastic.”
For the ultimate in individualism, some companies will even work with a client’s architect. For Dalton, who had been looking into building a post-and-beam house, it was her architect who steered her in the direction of prefabrication.
“Our architect found out about Griffner Coillte and was impressed by their closed-wall designs and the guttering,” says Dalton. “I was impressed with their breathable walls. I hate the idea of walls lined with plastic — it’s scary living in a tupperware box. They also had beautifully made wooden windows.”
Griffner Coillte is a collaboration between an Austrian timber-home company and an Irish forestry company. Clients must contract a builder for the foundations, but after that Griffner says it can build to turnkey specification.
It takes the company one week to assemble a watertight house on site, and four to six months to provide the finished, turnkey product. Costs range from €160 to €180 per sq ft for turnkey, while a more basic specification costs €100 to €120 per sq ft (€100,000-€120,000, or €160,000- €180,000 for turnkey for a 1,000-sq-ft property).
“It is a kit, but it’s not,” says Sepp Bichler, sales manager of Griffner Coillte. “It’s all about quality. We have a closed-wall construction and we’ve adapted our system to the Irish climate. As soon as you step off a plane into Dublin you can feel the moisture in the air. Unfortunately, some companies don’t change their systems to take this into account and you end up with fungus.
“We have a cavity wall on the outside — it’s a breathing wall so that moisture slowly penetrates out, but not back in. We call it a third skin. It’s a very healthy type of house and we’re in the process of building a creche in Summerhill.”
For Dalton, the only difficulty about building a prefabricated home is that the preliminary stage makes a lot of demands on the client in terms of deciding how the house will be put together.
“There’s so much preliminary work and it’s difficult to visualise during that period,” she says. “From a tiny scale you’re trying to work out where to put the plug sockets. But if you can do that and think it through carefully, it’s fascinating for anyone with an interest in design.”
Huf Haus, 00 44 870 200 0035, www.huf-haus.de/en; Davinci, 051 820 426, www.davinci.ie; Potton/Heritage Timber Frame, 01 405 5914, www.heritage-tf.ie; Griffner Coillte, 044 933 7800, www.griffnercoillte.ie
