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4 Answers

Foam over Platon dimple mat on foundation

We are stumped at a stage in our building process. Winter is here and we need to deal with our foundation. Our site is dry dry dry, but we are not ready to just attach foam to the cement and backfill without any effort to damp/water proof the foundation.

We are essentially forced to use a mechanical system as the weather and temperatures (-10 degrees celcius and wet) are making any other sort of damp/water proofing impossible (as far as we know).

Asked By jessie pratt | Dec 11 12
7 Answers

Housewrap under outsulation foam

Can you tell me if the housewrap actually serves a purpose underneath foam board?

Asked By Joshua Terry | Aug 3 17
4 Answers

Root cellar ceiling — Rigid foam installation

I've seen many pieces of advice on here on fastening rigid foam insulation to basement walls, etc., but I have a somewhat unique fastening situation I'm trying to sort out.

Asked By Kevin F | Aug 16 17
7 Answers

Alternative to a Frost-Protected Shallow Foundation

I wanted to build my house with a Frost-Protected Shallow Foundation. I've got a set of plans that I've been running by builders, and most don't have any experience with them. The general response is "Foundations need to go down 42 inches around here."

The general design for the house is:
Single floor
12" Double walls with a bearing exterior wall.
FPSF Monolithic slab with full sub-slab insulation
Rochester, NY Climate Zone 5

I have a couple motivations for the FPSF:

1. I want the house to be accessible (not too many steps)
2. I don't really want a basement.

Asked By John Ranson | Aug 15 17
7 Answers

Raised heel trusses and window height in elevation

I am asking my builder to include raised heel trusses in my new house, though I doubt my plans reflect that in the elevations. So, what are the implications of this?
- Should window heights be adjusted?
- Overhang distances?
- How will this affect the look of the house?


CZ3A, Greenville, SC

Asked By Norman Bunn | Aug 9 17
10 Answers

Plumbing question: Drainage vent for tiny house not hooked up to septic

I’m at the plumbing stage for my tiny house on wheels. After hiring a plumber, I see that he has an aav vent for both the kitchen sink and bathroom sink, in between the wall studs.

1) Considering that I am not hooking up to sewage (composting toilet), do I even need a vent?

Asked By Grey Wolf | Aug 5 17
12 Answers

Retrofit of a cathedral ceiling

I am living in a Log Home in Madison WI. (Zone 5-6) with a vaulted Ceiling. (2x6 rafters R-19) I am hoping to redo the roof soon. I wanted to put on a layer or two of Rigid Foam. XPS or EPS. Ideally getting close to R-20 plus the 2x6 insulated cavity. I will then put a standing metal seam roof on top of the foam using furring strips.

My issues are this. I am concerned that I will be trapping moisture between the XPS or EPS and the Vapor retarder or Vapor Barrier that is most likely installed on the warm side of the house. Right behind the sheetrock and before the batt insulation.

Asked By User-6884681 | Jul 25 17
1 Answer

Installing wall exhaust fans at a downwards pitch?


I am installing a wall bathroom exhaust fan (Panasonic WhisperWall 70) directly in my external wall. I know that many people angle their ducts/pipes at a slight downwards pitch towards the exterior. There will not be any ducts, just the wall sleeve.

I was thinking of installing this bathroom fan at a slight pitch (even through installation instructions do not say to do so). Is there anything wrong with me doing this?

Asked By Rocky12 | Aug 9 17
1 Answer

How to detail vertical edge with stepped foundation

We’ve build a building in Costal Maine. The exterior is copper flashing, advantex sheathing, house wrap, rain screen and cedar shake. The building sits on a sloped lot. The foundation steps down the slope leading to vertical section of the exterior build up that are exposed. How should we detail this to make it look finished and not impede water movement. What we’ve done to date is caulk the joint between the concrete and the other layers. We are considering running a trim board along the edge and leaving the horizontal edges open to allow the rain screen behind the shake to breath.

Asked By Paul Tasillo | Aug 9 17
1 Answer

Foundation exterior insulation and front porch slab

I am trying to think through what the details look like when you have exterior insulation on the foundation and then there is a patio for the front door.

Is the patio poured against the exterior foam and then a sill extension is used? Similar to attached.

Or, what other methods have you used? Would you do them again?


Asked By Ben Woline | Jul 27 17
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