Friday, February 18, 2011

The Exterior Walls

The exterior walls of the net zero ready house will be made from a double stud wall filled with blown in insulation. The double stud wall is basically two traditionally framed walls placed a few inches apart which create a space in between for an extra thick layer of insulation. The exterior wall of the double stud wall will be the load bearing wall and will be made from 2 x 6 studs spaced at 24 inches apart. The interior, non-load bearing wall will be constructed of 2 x 4 studs also spaced at 24 inches apart.

A vapour barrier and drywall are attached to the interior wall. House wrap and siding are attached to the exterior wall. In between the interior and exterior surfaces will be 12.5 inches of insulation, likely dense packed cellulose with an R value of 3.8 R/inch, giving the walls an R-value about 47.5.

The double stud wall seems to be the most cost effective way of achieving the desired high R value. Using other methods and materials, such as ICFs or SIPS, may have resulted in somewhat thinner walls but would have been much more expensive.

The frame for the house will likely be prefabricated in sections by a factory framing shop, then transported by truck and assembled at the build site. The Europeans have got this down to a super efficient, highly customizable, assembly line. Here's a video:

I'm not sure how it's done here in Toronto but we'll find out soon enough.


  1. Dear _______?
    I noticed you were onour blog and left comments. Thanks.
    Wanted to let you know you house design is interesting - thanks for posting floor plans and so forth. I wish you all the best on your exciting project and hope to catch up with you more often as it continues to develop. Send me email if you like at
    I wasn't sure which way north and south are on your drawings - obviously the main windows are facing south, but exactly how south? And please le tus know a little more about where the project is to be - Toronto area, but around where? Reason is the rooftop terrace. In our area we are not allowed such a thing due to privacy issues 'overlooking'. This had a major impact on our design and directed us away from flat roofed buildings. Your net zero/passive design is lacking a major south-facing energy-catching surface - ie no place to mount solar panels if not on frames on the roof top terrace. - I suppose thats where it would go? Not that you need them right away, but certainly I expect ou are designing to incorporate them in future at least.
    I am also interested to find out what you find out about the prefab walls in the Toronto area.
    Again, Best wishes to you!

  2. name is Adrian.....Adrian Besleaga. it is good to see you here guys.

    about the house - it is located at the 400 and 401 intersection NW corner. front of the house is about 10-15 degrees off south. we're probably going to increase a bit the glazed area but we'll have to live with a "not so perfect" orientation.

    I think the design of the house will still change a bit because the city is giving us some hard time regarding the rooftop terrace so we'll probably have to give up the roof acces but will keep the flat roof as this would be the only way of getting enough space for solar panels with our orientation.

    we're also in the process of deciding on some shading solutions. we have several options and we'll update the blog as soon as we'll decide on those matters.

    for the walls....there are few manufacturers around toronto. kenttruss is one of them. phoenixbuilding is another one. I think is the fastest, most economical way of raising up the structure. we'll see if I got this one right....

    good luck,