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4 Answers

Air sealing the cap of a double stud wall

I am currently building a double stud home in NH and am in the process of air sealing all exterior cracks with siga tapes. Since my builder decided to build the interior portion of the double wall after the exterior, we were left with a 4 inch gap between the two walls at the cap. We will be filling the 12 inch cavity with dense pack cellulose, so this gap at the ceiling needs to be blocked off. We decided to fill the gap with strips of plywood which has resulted in cracks on either side of the plywood filler that I'm worried may leak air.

Asked By Chris Roche | Dec 13 17
7 Answers

Insulate a cathedral ceiling efficiently

I just bought a house in Northern NH, zone 6 that was built in 1987. The house is about 3300sq-ft on 2 floors, so about 1600 sq-ft foot-print. The main living/top floor is entirely cathedral ceiling.

Asked By James Bodell | Dec 11 17
6 Answers

Insulating Rim Joist Beyond Foundation?

Completely below grade basement in Zone 5.
Poured concrete foundation
Water barrier/proofing sprayed on foundation.
R-5 rigid foam applied to foundation (on top of water barrier)
Rim joist insulated with roughly r-7 rigid foam foil faced on both sides. Over the insulation (interior side) is a 1/2" piece of OSB. The floor joists butt into this OSB. The joints of the OSB were caulked.

Asked By BobTheWeekendWarrior | Dec 11 17
17 Answers

Does anyone have any experience with ductless splits for very low inside temperatures (3 degrees C)?

We have a church in the Ottawa Ontario area (zone 6A). The church is only occupied for about 1 hour a week. We are using a very old oil fired FA furnace.(about 80% eff. 164K BTU input). I did some measurements last winter when the outside temperature was -20C. The furnace ran for about 5 minutes each hour to maintain 3 C inside. Would I be able to use a ductless split to maintain the inside temperature during the week and use the oil fired system to bring the temperature up for Sunday morning?

Asked By SanfordAndSon | Dec 4 17
2 Answers

Efficient shower stall design: Airflow?

So I'm kicking around ideas for efficient shower designs. Our master bath will have a shower stall that is recessed with three tile walls, and one glass wall with a glass door panel more or less flush with the side of the bathroom.

The glass wall will have three parts; two stationary panels and a door in the middle.

Asked By Lance Peters | Dec 6 17
12 Answers

Double stud framing insulation

We are building our full time retirement home in zone 5 in Lakeside Arizona. We want to use a double studded framing system to take advantage of the thermal break option.. What are our best options for insulation? and what are the R values of each option listed. See attachment:
1:Open Cell Foam Insulation 2x4 primary Dense Pack Cellulose / wool insulation for 2x4 secondary wall
Option 2:All dense Pack cellulose or wool
Option 3 Use 2x6 with either open cell foam or dense pack cellulose or wool 5 ½ inches

Asked By r ferd | Dec 4 17
4 Answers

Solutions to inadequate insulation at truss heel

After recently reading "Prevent Ice Dams with air sealing and insulation" I know that I am not currently able to get the insulation I want at the heel of my standard trusses.

I will be building a double stud wall inside an existing structure, which will help increase the effective insulation at the inner top plate, but there will still only be approximately 9 inches of available space measured normal (perpendicular) to the roof sheathing where the trusses meet the (inner) top plate.

Zone 6a (Maine)

I have a number of thoughts:

Asked By Tyler Keniston | Dec 5 17
1 Answer

Exterior wall options for southern Manitoba

Good evening we are in the planning stages of building a new house. The builder has given us an option of 2x4 walls in the build. They can be upgraded to 2x8 with staggered 2x4s, or a double wall system 2x6 with a 2x4 wall. What would be some recommendations. I like the idea of the larson truss system. Would they build a interior 2x4 wall then add the larson system to the outside? What could be the potential cost differences between each option. I am curious about the R value for walls ROI.



Asked By Bryonfriesen | Dec 5 17
9 Answers

Ensuring a non-load bearing wall is as such (double stud wall)

Simple framing question (I think) pertaining to double stud wall construction.
Should anything be done to ensure that the 'non-load bearing' wall is truly not bearing any load, such as making it a bit shorter than the load bearing?

The specifics are as follows: A garage with concrete stem walls and interior slab. The exterior wall is load bearing on the stem walls. The interior wall (to be built) will be resting on the slab, therefore should not be load bearing. The load is a simple trussed roof, 24' oc.

Asked By Tyler Keniston | Nov 29 17
5 Answers

Zip R with corrugated siding rainscreen- need gap or furring?

I searched and saw a post here about using corrugated metal siding over rockwool insulation and it was said that a rainscreen gap is not needed because a drainage plane is already there.

Would it still be true for corrugated metal (vertical or horizontal) over a zip wall system?

And if so, can the siding (metal) be screwed to the studs and sheathing directly without furring strips? i.e. framing/cavity insulation (R19) - Zip R5 wall sheathing - vertical corrugated metal siding.

Asked By Bernard Lam | Dec 1 17
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