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2 Answers

Smart Membrain with Mineral Wool

Using Thermafiber Mineral Wool in 2x6 stud cavities. Planning on using CertainTeed's Smart Membrain before hanging drywall.

1.) Is this the best idea in terms of proper product use and installation?

2.) Will stapling the Membrain to my studs cause any issue?

Asked By Nicholas C | Oct 18 17
0 Answers

Plywood sheathing over rigid foam.

THIS IS LONG BUT PLEASE BEAR WITH ME. Any advice on this project would be greatly appreciated! My home is located in the 6A zone. To start I purchased a home 3 years ago and decided I wanted to replace the windows and doors. The house was built in 1978. Upon further inspection of the home (which my home buyer inspector did not catch) I discovered that my house does not have any wood sheathing. It was built with 1in blue tounge and groove styrofoam board and had aluminum siding attached to it nailed to the wall studs. The rigid foam was never taped at the joints either.

Asked By rg14 | Oct 18 17
9 Answers

Can my outdoor minisplit unit benefit from a solar cover in harsh NY winters?

I am brainstorming a greenhouse type cover over my outdoor unit to keep it warmer in the winter to maximize its ability to heat. There are clear corrugated roof tiles at my local home store I am thinking of fashioning into a roof over the unit outside, facing South with possible partial sides. I am aware it needs air flow. My hope is to keep the outdoor unit warmer to avoid it getting too bogged down in the cold. It is a Fujitsu 15RSL3H made for extreme cold.

Asked By PamNYWinters | Oct 14 17
19 Answers

Are my minisplits modulating or short cycling?

Hello- first of all this site has been an incredible resource. I did most of my own research in adding 4 mini splits to my 1940's home. It was primarily for AC and heat for the shoulder seasons as we really enjoy our 1 pipe steam heat (although older boiler). I went with 2x Fujitsu (not XLTH) condensers with 2 heads each. A 12k per floor (open kitchen area, top of stairs, attic playroom), and 7k in the master.

Home has been retrofitted with new windows, open cell in the rafters, blown-in in the walls, etc...so definitely on the tighter side for it's age.

Asked By Kjmass1 | Oct 4 17
1 Answer

Low-ceilinged small bathroom in Zone 4, built in 1930: How to insulate?

The home has a metal roof with good dow corning underlayment. It is sloped and is a low ceiling at outside wall. I wanted to use Closed cell spray to Insulate . I have been closing up all soffit vents. I have to gable vents on house. My concern is having roof deck rot. Should i leave a 1/2 inch gap and vent to attic ? The area is a wrap around porch connected too main house that has been closed in over the years. The ceiling joists rest on top plate of main house.

Asked By Greenconfusion | Oct 18 17
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?

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.

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?

Asked By William Costello | Oct 16 17
5 Answers

Heat loss, can lights in cathedral ceiling

The information about replacing or retrofitting can lights with LED fixtures has been really helpful. However, I have a cathedral ceiling with what I think are standard can lights, with a diameter of 7.5" within the can, and about 9.5 " total diameter including trim--the ceilings are about 18' high so I am having a difficult time getting to one to carefully measure.

I cannot find anywhere residential can light LED retrofits for this size. I've looked at what Cree offers, as well as Home Depot and Lowes, and they all max out at 6".

Asked By JWBDSR | Oct 17 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).

Asked By Phil Ray | Oct 17 17
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