PASSIVE HOUSE THE ULTIMATE IN SUSTAINABILITY

A house with no furnace…in Canada? It sounds ridiculous, but it’s true. The Austria House in Whistler is what they call a PassivHaus, in layman’s terms, sustainability on drugs! The first of it’s kind in Canada, this house is so efficient that it requires virtually no active heating or cooling. Initially used by the Austrian Olympic Committee, the building is now home to a cross-country ski and cycling centre.

So how does it all work? Well, the major reason why your typical Canadian home requires an active heating/cooling system is due to temperature transfer. The loss of heated air (in the winter) and cooled air (in the summer) occurs at what’s termed “the thermal bridge”. These are areas such as windows, doors, walls, foundations. Passive houses are very different in their construction and are able to prevent this conduction of heat or cold.

In regards to the foundation, a passive house has a rather thick layer of foam between it and the earth. Therefore the heated (or cooled air in the summer) is not lost to the earth, but rather maintained in the thermal mass of the foundation.

Eliminating conduction by means of a thermal mass doesn’t stop at the foundation however. A passive house will also be constructed with solid wood R-50 walls (18” thick), an R-70 roof, perfectly sealed wood vapor barriers (free of punctures from electrical boxes, staples, and screws), specialized triple pane windows, and flawlessly sealed doors.

Surprisingly, a huge factor in the airtight quality of these homes is in this wood (yes, I said wood) vapor barrier. Typical vapor barriers can have hundreds, if not thousands of penetrations that create that thermal bridge we were talking about. These unusual plywood barriers are anywhere from 2.5 to 6 times more efficient than your standard poly style barrier because the joints are sealed with a specialized tape and the panels are installed without penetration.

Not only is the thermal mass considered, so is the indoor air quality. The construction techniques eliminate the need for toxic glues and chemicals, and instead use natural products. There is also an active ventilation system that leads to a significantly higher indoor air quality when compared with typical construction.

» Looking for an Interior Designer who can help make your home or office environment more sustainable? Contact Leigh at Hatch Interior Design located in Kelowna, BC – she’s an experienced LEED consultant with a love for eco-design.