When I was in Poland I met with several different companies about their businesses and technologies. One of the companies was Norpolhaus, a joint Norwegian-Polish venture. Andrezej Król, is the president of the company and spoke to me about their activities.
Wall construction: Norpolhaus builds custom, prefab, Passivhaus certified homes inside a factory in Poland. They can build up to 50 homes per year and currently are building around 18 per year. Most of those homes get shipped to Norway with the rest going to Sweden and Poland. The homes are made from FSC wood shipped in from Sweden. When you look at a cross-section of one of their walls, you get a good understanding why these houses receive Passivehaus certification even in Norway. From gypsum board to the outer finish which in the diagram is an acrylic plaster, the wall comes in around 34cm thick. That’s over 12″.
wall based on wooden structure C24 + system plaster (Fig. 1 wall with links; sequence of layers in a cross-section from inside to outside
plasterboard or gypsum-fiber board mounted on a wooden grillage, 45×45 mm
45×45 mm wooden grillage
mineral wool, 50 mm thick, constituting the core of thermal and acoustic insulation
mineral wool with thickness of 200 mm constituting the core of thermal and acoustic insulation, filling the space between the beams of construction of wall framework
wall framework made of Swedish structural wood C24 with cross-section of 45×195 mm
cured insulation board from mineral fibers or wood fiber constituting an additional thermal insulation layer and wind insulation
decorative, acrylic system plaster (9) (Source: http://www.norpolhaus.com.pl/walls)
The company uses advanced computer software to make sure the wood frames are cut and fit with each of the other parts precisely. Doing this kind of precision work is a lot easier in a protected, dry factory environment than outside where the elements can play havoc with your materials — especially the wood which will swell and warp when wet. Once all the pieces are built, the building is shipped in pieces to the site. Foundations are made of insulated concrete forms. After the walls and roof are erected, the company will perform a blower door test to find any air leaks they might have missed. Norpolhaus will also make your kitchen cabinetry, install all appliances and bathroom fixtures and use wood or fiberglass windows, whichever the client specifies.
Cost: When I spoke with Mr. Król, he was looking for Canadian partners. I asked how much he thought it would cost to build one of his houses and ship it to Canada. We worked out a very rough price, translating from Euros per square meter to Canadian dollars per square foot. A very rough estimate came out to $225 per square foot, which includes the kitchen cabinetry but does not include appliances, shipping, import and other taxes, foundation pouring, bathroom fixtures and finishing, flooring, or finishing. In addition, because we run on a different voltage system, the company would have to familiarize itself with Canadian electrical code, and have the relevant wiring and outlets shipped over to Poland for installation. Perhaps the price per square foot could come down if a developer committed to a certain number of homes, but maybe the better lesson is that doing custom prefab passivehouse certified homes is possible. Norpolhaus takes prefab to a new level.
Timing: Once the design has been finalized it takes about three weeks to build in the factory. It takes another three weeks to erect on the site. Finishing will take the rest of the time. In Europe these homes arrive and are installed on a completed foundation and finished within three weeks (excluding shipping time).
For more information, please visit the Norpolhaus website.