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3 Answers

Frost-protected slab on a moderate slope

I've been reading through the "Revised Builder’s Guide to Frost Protected Shallow Foundations" (http://cdnassets.hw.net/10/9d/3808b4b94676968c59b8548815f3/revisedfpsfgu...) and notice that they recommend FPSF on "low slope sites." I'm assuming that this would preclude using on a site of about 15% slope, but not sure what is generally thought of as "low slope." Any thoughts on FPSF on a 15% slope (Zone 5A), building is a split level with slab on grade, double stud walls with a concrete foundation wall serving as the uphill wall on the house and garage.

In Green building techniques | Asked By Ethan T | May 21 17
1 Answer

Heating a "near passive" house?

Hi everyone, I am currently mid way through the design of the home we will soon build. Coming from a traditional carpentry background and this will be our first 'superinsulated' build. We are not going for passive cert. but building with passive methods and ideas.

House is 2 levels, Walkout basement with lots of south facing windows. 2800 sq ft total.

We are in zone 6B in BC Canada, and aiming for wall R40 roof R60, using the dual stud wall method with cellulose insulation.

Planning to heat the house with a wood fired boiler, and having electric as backup for when we are not home.

In Energy efficiency and durability | Asked By user-6850466 | May 20 17
3 Answers

Do we need housewrap?

Building a new home in Hanover NH. Advantech sheathing will be taped. Then 2 1/2 inches of XPS will then be applied and taped. Then firing strips, then Hardy siding.

Initial plan was to place house wrap on outside of of XPS. Our builder says that perhaps house wrap is not necessary, given the tape on sheathing then again on XPS, but he is willing to add it if we prefer.

Is there any advantage to house wrap with this construction method?

In GBA Pro help | Asked By Frank Torti | May 21 17
10 Answers

Adding rigid foam above rafters but below ventilated roof deck

Hi all, wondering if this plan will work:

Climate Zone 6,Nova Scotia Canada
Simple geometry of roof.
Trying to create a ventilated roof system.

Rip off rotten roof sheathing.
Lay 3inch EPS rigid foam over top of rafters that are every 24 inches. R11-12
Planning on screwing on 2 by 4s on the flat from eave to ridge right above the rafter, effectively sandwiching the EPS foam between the rafter and the 2 by 4s.
Screwing on 5/8 plywood as roof deck onto the 2 by 4s, creating a ventilation gap between eps and roof deck.
Adding Nova seal as Ice and water shield.

In Energy efficiency and durability | Asked By user-6848033 | May 20 17
13 Answers

Residential frost-protected shallow foundation in central Mass.

We are planning to provide a monolithic pour frost-protected shallow foundation (FPSF) for a single story 1300 sq ft 2 bedroom home in central MA. Air Freezing Index is 2000. I have read through many different case studies, research papers, codes, etc and there is a bit of conflicting and locale-specific info so I am looking to see whether I understand what is required here. I am a newbie owner-builder. Any constructive criticism would be appreciated, but I don't want to foment any religious wars.

In Building Code Questions | Asked By Kenneth Gartner | Sep 2 16
6 Answers

Eliminating musty odor under a low-sloped (flat) roof

Hi Folks,
I have read all the info that I can find about low slope flat roofs, insulation and the possibility of venting.
But I am still unsure of how to proceed with my house problem.

In Energy efficiency and durability | Asked By Steverts | May 17 17
6 Answers

Best way to insulate crawl space in new build

Hi. I've asked this question before about an existing house, but now I'm building a new house and would like to make sure we get this right. Thank you to everyone who contributes here. Your insight is beyond helpful.

In General questions | Asked By Cherylann Schieber | May 19 17
2 Answers

The shoulder season with mini splits- Do I select heating or cooling or shut it off completely?

I Recently hired a contractor to install a Mitsu MSZFH15NA indoor unit with MUZFH15NA outdoor unit to be the sole source of heat and AC for a 1970 single floor ranch, 900 sq. ft, open concept with cathedral ceilings about 12 feet tall, in the Cape Cod, Mass area..

Previously, a pellet stove was the source of heating and a window ac unit for cooling. Both which worked well in terms of comfort and efficiency when paying the electric utility at months end.

In Mechanicals | Asked By James Someone | May 20 17
8 Answers

Microwave: High or low?

My wife and I know the pros and cons of having the microwave over the range (more cons than pros) but don't have any experience with the microwave under the counter.

What are your thoughts about putting the microwave under the island counter (safety, convenience or inconvenience)?

In Interior design | Asked By Mark Walker | May 12 17
4 Answers

Does Grace Ice & Water adhere well to OSB sheathing?

We will soon be adding the OSB sheathing to our new build, and I intend to build a PERSIST wall system.

Based on this particular quote in an article on this site: “Peel-and-stick tape on OSB doesn’t work without a primer.” ...along with a video of building a PERSIST house in Austin Texas, in which they coated the OSB with some sort of primer before applying the peel-n-stick, I am wondering if this a crucial step? Did I miss that detail in the PERSIST article or was it omitted for some reason? I was planning on using Grace Ice and Water Shield. Many thanks!

In Green building techniques | Asked By John Peeper | May 19 17
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