Q&A: A Forum for Green Building Experts and Beginners

Q & A Instructions

[Click map to enlarge]

The GBAGreenBuildingAdvisor.com web site has a wealth of articles on a wide variety of construction topics. Before posting your question, you may want to check out the articles on this page: How To Do Everything. You just might discover an article there that provides the information you seek.

Please register for a free account or sign in to ask and answer green building questions.

If you want to post a question, the usual rules of courtesy apply:
1. Be nice.
2. If you can't be nice, be polite.
3. If you can't be nice or polite — well, please be brief.

To attach a photo or illustration: Under the box labeled “More explanation,” look for the words “File attachments.” Click that, and you should be able to attach a photo.

Thanks for joining the conversation!

3 Answers

Bonus Room Above Garage Insulation - SE Michigan

I know this has been talked about a lot but my bonus room above the garage is freezing in the winter especially the floor. The room has knee walls also. I am looking to get the room spray foamed and have had 2 guys come out with 2 different options and its a bit confusing. Options are below:

Current status - I ripped out the garage ceiling dry wall and pulled all the insulation down. There was differently a gap between insulation and the floor in spots and just not insulated good in my opinion.

Option 1

Asked By swdude12 | Oct 19 17
14 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
3 Answers

Are furring strips needed for Galvalume siding?

I am about to install metal siding on small guest house and not sure I need to have furring strips. Most of the information I’m finding discusses metal roofing installation, or vinyl siding.

As the structure sits now, all exterior walls are framed with 2”x6” lumber 24” OC, OSB sheathing with taped seams, 1” polyiso foam sheathing, and Tyvek house wrap. Interior wall space will be insulated with mineral wool insulation.

Asked By Andrew Sisson | Oct 19 17
1 Answer

Polyiso and loose-filled cellulose insulation in cathedral ceiling

I have a home built in the 1950s in Tennessee. The PO closed attic to make a large family room, bathroom, and full bath. No insulation has been installed in the knee walls or the slope of the ceiling. The space behind the knee walls is roughly another 800 sq. ft. of space, that I would like to turn into conditioned space.

Asked By LRSeries | Oct 19 17
4 Answers

Stopping moisture / condensation build up on bathroom walls

75+ year old new Home. Bathroom approx 75 square feet was recently remodeled. There was originally a dropped soffit area above the shower. It was removed and the ceiling was taken up to the ceiling line of the balance of the room. Glass shower doors were added in place of rod and curtain. Walls and ceiling were repainted. A light fan combo was installed and a second fan was added later. Both fans were tested for flow and there is 80+ cfms between the two. Even after the second fan was added there is a tremendous amount of sweating on the 3 interior walls and ceiling.

Asked By Merritt50 | Oct 19 17
0 Answers

Looking for local GBA contractor in Chicago IL

Hello, I am looking for someone in the Chicago IL area to help guide me in building an underground roof. Do you have a list of contractors that are Green Builders in the IL area? Thank you!

Asked By bawhitn | Oct 19 17
2 Answers

Recognizing unsafe vermiculite removal

We have lived in our 1960s built home for about 5 years, and are trying to make some improvements. A low ceiling needed to be opened, maybe add some skylights, as well as redoing electrical work in the ceiling.

Asked By iinva | Oct 19 17
3 Answers

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
3 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
7 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
Register for a free account and join the conversation

Get a free account and join the conversation!
Become a GBA PRO!