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0 Answers

Use foam board underneath fountain footer?

I am installing this fountain in PA:

I don't want to dig 36 inches to the frostline.

Can I dig 2 feet, put tamped 3/4 clean stone, place XPS foamboard and then pour concrete?

Asked By John Sean | May 22 17
6 Answers

Kerf channel and thermal bridge

I am working through a shed roof design for a small shop and I have always liked protruding rafter tails. Obviously, I know these days they have been entirely eliminated due to the thermal bridging.

I will ask one question though and show a couple drawings. What if one were to cut a deep enough channel or kerf (may not be the right term) along the exterior face of the envelope (in my case, a SIP)? And then, if that channel (all the way around BTW) were filled with a foam of some kind.

Asked By John Brown | May 20 17
3 Answers

Frost-protected slab on a moderate slope

I've been reading through the "Revised Builder’s Guide to Frost Protected Shallow Foundations" ( 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.

Asked By Ethan T | May 21 17
16 Answers
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!

Asked By John Peeper | May 19 17
13 Answers

Zone 4 Build--Bottom to Top

Hello all

I am building a new home in the mountains of western NC, Zone 4. Four seasons there, lots of rain. We will be building on a 31% grade with one main level and one lower level(for some reason they hate to call them basements there!). If you don't mind, I would like to start at the bottom with my proposed build and work my way up. I wanted to get this all figured out before I go to the architect and builder.

Asked By Kevin Spellman | May 15 17
4 Answers

Foundation question: Slab on grade or monolithic?

I am going to build a small 12 x 16 Timber Frame house in the Intermountain West - Zone 6. I attached a rendering. One question I have is about the foundation. I think I am confused about the terminology that I hear. Would it be preferable to do a monolithic slab or a slab on grade with a stem wall? I know there are lots of details here and in Lstiburek's Building for Cold Climates but I'm wondering what a pro might recommend (no basement or crawl space).

Asked By John Brown | May 17 17
18 Answers

How important is a thermal break between a house foundation and an attached garage foundation?

Our footings were poured today for a new house and attached garage. The walls of the basement foundation (9') and garage foundation are scheduled to be poured next week.

Looking over the plans, our concrete sub is worried about the 7" thermal break between the basement and garage foundations (no physical connection) as currently drawn on the plans. The separation is there in order to allow us to attach 5" of Roxul Comfortboard 80 to the basement foundation (we'll be doing the same for the whole exterior perimeter of the basement foundation).

Asked By Eric Whetzel | Dec 2 16
3 Answers

Strata International

I've come across a new to me building technology which is being utilized in the Phoenix area. It is essentially the inverse of ICF. 8 inch EPS core for the walls and 12 inch for the ceiling with both sides finished in a shotcrete like concrete product. The system comes from Strata International (

Asked By Jeffrey Savage | May 17 17
15 Answers

Final design: Roof, walls, and floor

So getting final details of a new build in Zone 6 (Osaca, ON) Hopefully pretty good house , that will be Net-Zero.
Any comments or suggestions before I finalize this? Thanks !!!

Roof setup:
Standing seam metal roof
Blueskin self-adhered membrane
5/8 plywood
2” air gap
attic truss with raised heal
24” minimum blown in cellulose
1/2” drywall
latex paint

Wall setup Outside to Inside:
Vinyl Board and Batten Siding
1x4 furring strips mounted horizontal 12” OC
2 layers of 2” Silverboard EPS taped seams
Blueskin VP100 ,maybe something else?

Asked By Dave B | Apr 4 17
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