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6 Answers

Vapor barrier needed if interior walls are horse-hair plaster?

I plan to put new, pre-stained cedar shingles on the exterior of my 1920s bungalow this spring. This is the only side of the house that hasn't been renovated. Earlier renovations to other parts of the house revealed tar paper under the shingles, so I assume we'll find the same thing under these shingles. The interior wall is horsehair plaster and there is no insulation (this is the only exterior-facing wall in the house that still has horse-hair plaster). I've read some confusing posts about Tyvek/Typar and moisture barriers. Do they create moisture problems with horsehair plaster?

In Energy efficiency and durability | Asked By bonbar15 | Oct 16 17
8 Answers

Summer cabin retrofit

We bought a 70's tongue and groove cathedral roofed cabin in Meyers Ca. I think the winter is a region 5. The current shingles are unfortunately in too good a shape to tear off but ultimately i will put 6" of cc foam and a cold raised seam roof with some sort of screen to prevent spark entry. I have spent the last 60 days of spare time addressing the down slope water issues by installing a french drain and water proofing the foundation and removing the mostly fallen fiberglass from under the 4' centered beam crawl space.

In Energy efficiency and durability | Asked By Mike Wanless | Oct 16 17
1 Answer

Capillary breaks and code

This is an offshoot from my previous question about choosing a product to use for the capillary break between the footer and the poured concrete foundation wall ...

In speaking with a rep from Tremco Sealants about using their Tremproof 250GC product for this purpose, he mentioned that we might want to check with our local building official to see if they have any problem with having a membrane in the cold joint between the footer and the wall.

Anybody ever heard of this being a problem?

In Building Code Questions | Asked By William Costello | Oct 16 17
1 Answer

Exterior rigid foam and interior mineral wool for hip roof

I am planning some envelope and HVAC upgrades on a 1958 brick-veneer home in climate zone 5a (Southeast Michigan). Would the GBA community be willing to check/advise my insulation/roof plans?

Right now I'm looking at the 2nd floor which has three bedrooms, a hall, and a bathroom; I have a manual J calculation complete.

My plan is to bring the attic into the conditioned space and insulate to R49. The attic will not be living space or even used for storage. It's currently unconditioned and contains ducts for air conditioning (heat un the house is via hot water baseboard).

In Energy efficiency and durability | Asked By Phil Ray | Oct 17 17
1 Answer

Insulating sloped ceiling in old house

We are reinsulating the attic of our 100 year old home but are dealing with a difficulty. The top floor has a sloped ceiling from about five feet high to the flat ceiling. When we bought the house, the previous owner had stuffed this from the attic area with batt, which had blocked the soffits and caused premature aging of the roof. We unblocked the soffits, reroofed and added a ridge vent. We are now in the process of replacing the wood shavings and need to be able to insulate this area.

In Energy efficiency and durability | Asked By Heather Moore | Oct 17 17
12 Answers

Hundreds of flies in my bags of Roxul insulation. Is this a concern?


I stored my brand new roxul insulation ( still in wrapping) in the barn and has been sitting on a raised shelf for six months. I go to open all the bags to insulate today and there are hundreds of flies inside the bag, and alive. It's almost like they were all drunk (I assume from the insulation smell). My donkeys use this barn and the barn has a lot of flies in general.

In Green products and materials | Asked By Tom87 | Oct 17 17
8 Answers

How to utilize cool basement / crawl space air to help cool the house?

I have a house on a hillside about 1300 sq. feet with a walk in basement/crawlspace under the entire house. I am located in Atascadero, CA 93422, which has hot, low humidity days in the summer but cools off rapidly in the evening. It is extremely rare that I need cooling in the evenings.

In Energy efficiency and durability | Asked By Cuj Monguy | Oct 16 17
1 Answer

Sauna inside home

I was in a home earlier this summer where the homeowner had decided to put a sauna on the second story of his home. The home was new construction with the homeowner acting as the general contractor, and is located in zone 7, less than 100 miles from the Canadian border, and is in a rural location with no inspections. Construction is code minimum 2 x 6 framing with osb sheathing, R-21 fiberglass bat and class 1 poly vapor barrier, house wrap and smart siding. No rain screen. The vented attic was not insulated when I was there, but will most likely be R-49 blown fiberglass.

In Energy efficiency and durability | Asked By Randy Williams | Oct 17 17
7 Answers

I have a problem with humidity management during winter in my off-grid secondary home

When we get there the air inside can be as low as -20C so when we go back all the humidity we produced is collecting-condesing on the vapor barrier (Isofoil).

The building is 3 years old and was built quite tight by myself. 2 floors, 28x32, heat source wood stove only.

In General questions | Asked By Pierre Levasseur | Oct 15 17
2 Answers

Swedish platform framing and other non-conventional framing practices

I'm in early stages of planning my new home and I want to build using swedish platform framing priniciples as described in the "new american wall" articles on this site and the lamidesign site.

I'm curious, for anyone who has built with this framing method or other non-conventional framing practices, what additional challenges did you face with respect to plan approval and framing inspection, and how did you overcome them?

Any and all words of wisdom are welcome!


In Building Code Questions | Asked By user-6919167 | Oct 16 17
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