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5 Answers

Building codes

I often see posters refer to building in areas with no codes. Here in Canada, although we have areas in which there are no permits or inspections, the building codes are enacted to cover the whole of each province or territory. People building in areas where the codes are not enforced have the same obligations to follow them as elsewhere.
Are there areas in the US where there are no codes and you are free to build as you like?

In Building Code Questions | Asked By Malcolm Taylor | Sep 2 15
1 Answer

Can construction foot traffic on the roof dislodge or break the seal between the foam and the sheathing?

I am having the underside of my roof (flat roof-1/4"/12) sheathing sprayed with 2" of closed cell foam (flash/batt). I am concerned that construction foot traffic on the roof will dislodge or break the seal between the foam and the sheathing. There is quite a bit of flex in the roof sheathing. Is my concern valid?

In Green building techniques | Asked By keith messick | Sep 3 15
4 Answers

Roof ventilation ideas

I'm trying to add attic ventilation for my whole house fan, as the manufacturer states that I need a total of 4.4 sq. ft. of free air. I currently have gable vents, but they're located right above a window and the attic air gets sucked right back into the house (even when the window is closed, to some degree, and I'd like to open that window anyway). So I'm thinking of sealing off the gable vents and getting all the ventilation from the roof.

In General questions | Asked By Robert Shelton | Aug 26 15
8 Answers

Attic insulation upgrade

I'm struggling with getting the correct answer on how to proceed with upgrading my attic insulation.

I live in Pittsburgh PA climate Zone 5A.
My existing attic space has batt insulation on the floor with no air barrier and is vented at the gable ends.

I would like to spray foam on the underneath of the roof deck sheathing in-between the truss joists and on the gable end walls to meet the required R38.

I'm struggling to understand if I should use open cell foam or closed cell foam.

In Green building techniques | Asked By Forrest Watson | Sep 1 15
2 Answers

How were the IECC Climate Zones maps developed?

Were high resolution zone maps developed and then adjusted to match the county boundaries—perhaps with a generous safety margin—or something different entirely?

My brothers' houses, 150 feet apart, are in different counties. One house is in Zone 3 (Johnston County, NC), the other in Zone 4 (Harnett County, NC). Should my Zone 3 brother be concerned that he's really experiencing Zone 4 conditions (and vice versa)?

A generous safety margin might imply that some true zone 3 climate locations are well into Zone 4 map areas which can have a large impact on those with a tighter budget.

In General questions | Asked By Stewart Akerman | Sep 2 15
5 Answers

What mechanical system makes the most sense?

I am in a zone 4a Kansas City Missouri. In the heat of the summer it can get up to 95 with high humidity and it doesn't cool down at night.

We are building a 3500sqft ICF house with R-24 walls. (We have the labor and resources for it to be the most affordable option) and a R-60 SIP roof, cathedral ceiling. We are thinking about building with a 4' crawl space, unvented, 20 mil vapor barrier. Our windows and doors we are sourcing from company's in the U.S. which build to the PassivHaus standard.

I have a few questions:

In Mechanicals | Asked By Jordan Schiele | Sep 2 15
4 Answers

How to reduce the humidity in my home?

I live in a 1200 sq ft. mobile home and heat with electric space heaters. I do not tolerate forced air due to severe chemical sensitivities (it is propane), so all grills and ducts are blocked off. The humidity in my home runs between 40 - 50 % which is too high. I keep it closed up tight to keep out wood smoke and dryer sheets from the many close neighbors that I have. I am interested in the eGO for my laundry room, and wondering if the air coming in and out can be filtered with more than what it comes with. I am also open to other suggestions.

In General questions | Asked By Suzanne Lippuner | Sep 1 15
1 Answer

Seeking advice on insulation and membranes for an exposed wood structural roof

I am working on a little house extension located in Toronto Canada. We are shooting for an exposed wood structure, with the insulation (required r-value 31) outboard of the roof's diaphragm which will either be tongue and groove or a very thick plywood.

I am very unclear on where my vapour barrier should be located - I was taught that the membrane needs to go on the warm side of your wood studs, in a conventionally framed wood house. In this scenario there is nothing below the warm side of my structure at the ceiling - there is analogy in the condition I am working on.

In General questions | Asked By Guy Debord | Sep 1 15
10 Answers

I am considering getting solar panels on my roof

I am considering getting solar panels on my roof and have quotes from 2 different companies. Is there anywhere I can go to get help on determining which are the better panels?

In Green products and materials | Asked By Dave Sanda | Aug 31 15
15 Answers

XPS or PVC under base plate

I'm looking to start framing in our basement. The house is 15 years old, and did have some water leakage (some small puddles could form during big rains... We had crack injections done this fall to alleviate the issue), but no flooding yet (knock on wood).

I thought I read somewhere that you could use XPS insulation to put under the base plate of the wall. It seems like a good idea (a 1" insurance policy should the basement begin to flood).

In Green building techniques | Asked By Andrew Wayland | Feb 22 15
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