TERRELL WONG - PRINCIPAL ARCHITECT B.ARCH. OAA
12 St Andrews Gardens, Toronto, CA
416-898-8089
Doors & Windows
Sustainable Architects Toronto
These holes in your building should not be poorly insulated or have leaky frames. 30% of heat loss from windows is due to the frame. This is why larger windows which have smaller frame /glass ratio are more energy efficient. Fixed windows have thinner frames and therefore are more efficient than operable windows.
We insist on triple glazed windows with European hardware for all our projects. The high R value, thermally broken frames and superior hardware are the key to comfort.
Passive House requirements are such that the temperature difference between the exterior and the interior at the window is less than 3°C. Greater than this convection currents (air movement/drafts) can occur and cause discomfort. Currently our source of European Passive House windows is better made and less expensive than anything we can get locally.
Having said all this, windows are a very expensive way to capture heat in your home. Prudent use and placement of windows are keys to a comfortable house all year round. Even the doors on your home can be windows. Where possible we use triple glazed doors as the most economical option, where the client prefers a more traditional solid wood door we have Passive House options.