Completed in 1996 near Stuttgart, Germany, das minimalhaus was our first R2000 prototype, designed while I was still an architecture student at the University of Stuttgart. Ulrich Queck (qbatur.de), a friend and extraordinary carpenter and architect developed my sketches for the concept from ‘das kubushaus‘ into a functional program for the client and built it the next Summer. This was when the ‘Neidrigenergiehaus’ standard was coming into full force and ‘Passivhaus’ would develop as an offshoot from that static, spreadsheet-based approach to whole-house thermal review. The concept has functioned flawlessly for 23 years and even supported the expansion as anticipated by Ulrich.
Design for Disassembly: Part of the design concept was 100% reversibility of all connections, drop beams, screwed connections, no glues or caulking. All interior plywood finish panels were gasketed to wall studs using neoprene tape. After 23 years, when the owner decided to create an addition, one entire exterior wall was simply unbolted, and all materials from the former exterior wall were re-used. The measures for anticipated future disassembly meant a very clean working surface for the new addition, and the tidy storage of removed materials without any need for heavy demolition equipment on site, minimized dust, and no need for a dumpster or even a trip to the dump.
This 100% CO2-neutral home features integral PV that produces 400kWh more electricity than it consumes annually. The home is heated by 3,000kWh (annual) of carbon-neutral wood heating (soapstone stove) complete with an integral hot water loop and solar DHW. That’s equivalent to 0.8 of a cord, or 3 cubic metres of local birch per year. Other features are air-tight gasketed plywood interiors, 30cm of cellulose insulation in the walls, triple-glazing, Larch wood rainscreen cladding and optimized Area to Volume ratio (cube). The owners are still as happy with it as the first day they moved in. Zero carbon footprint for 23 years. TEUI is 24.76 kWh/m2*yr, and 36.19 after the renovation. (Just to compare, Passivhaus is allowed 15kWh/m2*yr heating energy, so we’re double that, but it also allows a grand total of 120kWh/m2*yr, which we are well under) We plan a re-boot of this design in Ontario slated to start construction in Spring 2019.