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2 Answers

Foundation wall drainage

To create better drainage, I'm considering extending the aggregate from around the drain tile up the foundation/basement wall closer to grade instead of just using regular soil backfill. I can't find much info regarding this technique online. How is this accomplished? How close to grade is the aggregate brought, and how wide is it in the trench? Trenches are a couple feet wide; that's not all stone, right?

Asked By Bryanw511 | May 7 18
1 Answer

Air control layer: Sheathing, Sheetrock, or both?

My question on making in ceiling speakers air tight got me thinking more about my air control layer. We are building a new home in climate zone 6A. The insulation strategy for the walls is 2x6 framing on 16" centers. Stud cavity filled with netted and blown fiberglass and 2.5" of foil faced exterior polyisocyanurate foam. The roof strategy has yet to be determined (based on overall budget) but the two options for the 2.5/12 slope un-vented cathedral ceiling are:
A) 14" TJI rafters with 5.5" of ccSPF and 8.5" of netted and blown in insulation

Asked By Steve Mackay | May 7 18
11 Answers

Foundation insulation & moisture protection

I would like to insulate and protect my basement foundation walls using a water based spray on waterproofing, XPS insulation board, and a dimple mat. In what order would they be fastened to the wall? I feel like the insulation should go on after the waterproofing for it to be effective as an insulator.

Asked By Bryanw511 | Apr 10 18
3 Answers

Air infiltration through sump pit

Ran a blower door on what should be an extremely tight home. However I am getting significant leakage through the sump pit which is essentially connected to the outside via the drain tile. (grading has not been completed on the property) I found some other air sealing to do, but i have never run into this situation. Do I need to wait for the grading to be done, or have the sump pit sealed?

Asked By Jeff Classen | May 4 18
11 Answers

Minimalist on top of slab insulation options

Hi all,

I have an existing 1970s structure with a 42" below grade basement slab. I'm re-doing the flooring in the basement (settled on cheap laminate over expensive stained and polished concrete) and am wondering about getting a tiny bit of insulation on top of the slab before I install the laminate.

I have a 91" ceiling height. so I don't have the head height to consider any of the lovely options described in the lovely GBA q&a here such as 2" of XPS and an inch of plywood.

Asked By Keith H | Mar 17 14
10 Answers

Spray foam roofline in stone house

I have a house made of dry-stacked stone (with a continuous layer of concrete parging on the outside, and mostly plaster on the inside of the walls, with some exposed dry stone in places the plasterers couldn't reach. I regard the concrete on the outside as a pretty good air barrier, and I am debating whether to complete the envelope by spray-foaming the underside of the roof-deck to R-32. Currently the roof is insulated haphazardly with R-13 batts behind a finished drywall dormer ceiling.

I worry about a few things before proceeding with the plan:

Asked By Jack Zylkin | May 3 18
11 Answers

Flashing deck ledger

So my build is getting closer to a go this spring, as plans are wrapping up, I'm trying to get the small details correct, I've learned on this site, these can come back to bite me if not done correctly.

So our house is single storey with a walk-out basement and full wrap around covered porch.
Walls are 2x4 stud 1/2 sheathing taped, 6" polyiso(2 x 3") ,Tyvek, 3/4" furring with vinyl siding , basement is 8" ICF(Logix)
so 13.5 " total width plus 2"x4" stud walls on the interior.

Asked By Dave B | Mar 12 18
21 Answers

Airtight envelope with in-ceiling speakers

Climate 6A. Planning on a pretty good house. R-60 roof, R-30+ walls and less than 1.5ACH50. We're planning an un-vented cathedral roof with low slope (2.5/12).

I have already specified no canned lighting in my ceiling but I just got to thinking about having in-ceiling speakers. I assume they are as bad or worse for air sealing and stack effect into my rafter bays?

Is there such a thing as a well sealed in-ceiling speaker or should I be looking at other options? Any recommendations?


Asked By Steve Mackay | Apr 26 18
8 Answers

New Hampshire wall assembly option help

Okay so I'm trying to make up my mind on which wall enclosure tech to use.

Background info:

Asked By tech1234 | May 1 18
2 Answers

Rigid foam insulation on top of a concrete slab

Weather zone 4 C (on an island in Canada just north of Vancouver). new construction of small cabin. the plan is to pour a slab of concrete on top of a bed of gravel over sound subsoil, then lay stringers of 2x4 on end with rigid foam insulation between the stringers. Top with 3/4" ply sub-floor and 1/4" nail-through oak flooring.

Decided not to put insulation under the slab because of potential infestation by termites / carpenter ants.

Asked By User-7062830 | Apr 28 18
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