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12 October, 2008
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Production line precision
Autumn 2006
Published:  22 October, 2006

Automated technology produces the components and then the frames are put together on an assembly line

Germany's timber frame home manufacturers have the UK in their sights. Stephen Powney reports from WeberHaus in the Black Forest

The image of the Audi television advertising ending in the German slogan “Vorsprung durch technik” has imbedded itself in the minds of a generation.

The subconscious message is that the Germans somehow produce things that much better. There is plenty of evidence – cars and kitchen appliances spring to mind. Even the country's football team has become synonymous with efficiency.

Now Germany's house construction industry is targeting the UK market. A wave of German timber frame home manufacturers have set up in the UK, spurred on by the impact of Huf Haus – which, when featured on Channel 4’s Grand Designs, gave the show its highest viewing figures – the government's modern methods of construction agenda and the growth in timber housing.

The biggest of these companies is WeberHaus, which has supplied more than 28,000 homes across Europe in the past 45 years and has been advised by Porsche Consulting as part of a “continuous improvement” programme.

The company's Bad Saulgau base is situated in the Black Forest near Baden Baden. From here, and from a second factory in northern Germany, 700-800 houses are manufactured off-site every year.

During its first year in Britain WeberHaus has established a partnership with experienced contractor William Verry Construction, with which it has enjoyed a double success in the government's Design for Manufacture competition. This tie-up allows WeberHaus to offer a turnkey package, including the various build processes, such as concrete foundations.

The company hopes to start work on its first UK house, likely to be a 3,500ft2 detached house, in the south-east in the coming months.

WeberHaus' construction system is closed panels incorporating doors, windows, insulation, electrical conduits, tiling, exterior finish and even shower fixtures.

The frames are produced on an automatic line, while customers can choose all their fixtures and fittings in the WeberHaus “Hall of Creation” containing everything from roof tiles to taps. “If a customer wants, we can do everything, even put up the curtains,” says the company.


House styles range from bungalows to avant-garde designs
WeberHaus has been learning about the UK housebuilding market through the development sector, and since April it has also been pushing self-build.

“We now know the structure of the market, which is totally different to Germany,” said WeberHaus international sales manager Jürgen Leppert. “There is a lot of demand in the UK market in developments and also in the bespoke market. We will happily compete with traditional brick building.”

He said the UK was characterised by big housing developers and pressure to find plots, while Germany had a high proportion of self-build and land being sold to the public by local communities. Also, UK house buyers tend to focus on the number of bedrooms, whereas square metres are king in Germany.

To meet UK customer requirements, WeberHaus is creating an additional 12 floor plans/house styles, with a choice of external finishes, including render, brick or wood.

It has also developed a new wall system (U-value 0.21) to satisfy the National House-Building Council, which demands a 5cm ventilated cavity. WeberHaus has made a major investment to take the system through the BRE certification process. And the company’s German wall (U-value 0.159) may also be used in the future.

Key to the WeberHaus offering is planning, production and logistics. The production process starts when a customer has agreed to buy a house and signed off all fixtures and fittings, including where electrical connections and light switches are to be situated. Orders are then sent out to suppliers for just in time delivery to the factory.


WeberHaus has been learning about the UK housebuilding market through the development sector
“It's like the automobile industry – all the parts come together at the same spot to be assembled,” said international project manager Sebastian Popp. 

The graded structural timber is locally harvested untreated pine, dried to a 15% moisture content. Treatment is reserved for special applications, such as sole plates.

Components such as windows and sills (made from marble for durability) are marked with customer names in the warehouse.

Automated factory technology cuts, drills, measures and adds marks to the timber components. The frames are then put together on an assembly line.

To give the frame rigidity, chipboard (16mm) is used for sheathing instead of OSB. A water vapour barrier and plasterboard are added and cutouts made for the positions of electrical sockets. Plastic tubing is fed into the cutouts and along designated routes for electrics, in order to house wiring installed on site. Positioning of sockets and specification of windows and floors are all done prior to house structural calculations.

Mineral fibre insulation (160mm) is filled between the studs and then covered with either timber/cement board or a 100mm wood fibre insulating board. If a rendered finish is required, a layer of cement is then added to the exterior face.

Metal and foam sealing strips are added to panels which connect with roofing elements, while plastic sheeting and rubber are attached to the bottom of ground floor panels.


Customers can choose all their fixtures and fittings from WeberHaus’ Hall of Creation
Doors, windows and other features are then installed, together with a further coat of render. The final render finish is always applied on site to cover connections.

WeberHaus' UK wall has an additional chipboard sheet on the exterior face (instead of timber/cement board or wood fibre), to which 50mm lathing is attached to create a ventilated cavity. STO Ventec board (12mm) made from recycled glass is attached to the lathings, followed by 4mm reinforced render, then the 3mm final render.

Solid timber floor joists are preferred to I-joists and are manufactured as cassettes, while roofing sections are also prefabricated.

Staircases are made in-house, with cutting, laminating, sanding and finishing operations turning raw wood into the finished product, which is craned into position on site.

In all, manufacture of a house takes about two days, then erection and waterproofing on site is often only one day – a process which WeberHaus demonstrated on video at

this year's InterBuild. Internal fit-out can start on day two, with the house ready for occupation after about a further 11 weeks.

For its UK developments, WeberHaus will be offering flexibility in terms of fixtures and fittings, but with a certain level of standardisation to maintain commercial viability.

Two developments in the pipeline are the winning Design for Manufacture schemes for William Verry. One is a distinctive “S” shape single linear development in Aylesbury, designed by Make Architects, comprising 102 two- and three-storey homes on a former Territorial Army site. The other is a 15-unit scheme in Hastings, due to go on site by the end of the year.

WeberHaus will encourage local sourcing of fixtures and fittings, with William Verry already having several tie-ups with flooring, kitchen and tiling companies. But self-builders can still choose their own fittings or source from WeberHaus in Germany.

Leppert believes the UK housebuilding industry needs a change of mentality.

“In the UK, the end user does not have the choice and for a price which is very high.

“We will be offering similar pricing but with a lot of individuality. We will give possibilities to people who want to invest in their dream home. They will have complete freedom of choice.”

Such choices include house styles ranging from bungalows, to villas, country houses and avant-garde individual homes.

There is also a strong environmental focus. WeberHaus has its own alternative energy centre at Bad Saulgau, showcasing solar and photovoltaic technology, as well as mechanical ventilation heat recovery and ground source heat pumps.

The company's Passive House has a maximum heating requirement of 15kWh/m2 per year, with no central heating system required. Heat is instead transferred through people/electrical appliances and by solar gain.

So, the big question is will the “Vorsprung durch technik” (“advances through technology”) approach adopted by WeberHaus and other German timber building companies be translated into success within the UK housebuilding sector? It will be interesting to watch.

It's housebuilding – but not as we know it.


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