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8 Answers

Does leaving a service cavity on the inside of a double stud wall make sense?

Would there be anything wrong with the following assembly? From exterior to interior: Siding, furring, rigid insulation, sheathing (air seal and WRB), 2x4 stud wall, gap, netting stapled to inner studs. 2x4 stud wall, and finally drywall. The outer 2x4 stud wall and the gap would be filled with cellulose, but the inner 2x4 stud wall would be empty to allow easy wiring and plumbing.

This design seems to have some clear perks. Removed thermal bridges. You get a service cavity. The inner wall supports the netting, so it won't need excessive stapling.

Asked By John Ranson | Aug 27 15
3 Answers

Attic Ductwork

I live in Nashville, TN climate area 4A

My issue is my attic gets so hot in the summer months and my heat pump runs a lot but does not cool very well. This is a duplex home with each side having around 980 sq foot living space.

Asked By Janice West | Jul 11 15
34 Answers

Re-roof and insulation question

I have a 22 year old home. It has a 25 year comp roof on it with 1/4" Foamcore insulation under it. I need to re-roof and wanted more insulation (thinking about 3/4" foam). Can I just run a 1" x 4" around the edge and put new drip edge and sheet over the old roofing with the foam and putt the new reflective comp roof over it? If so, what kind of foam do you recommend? Really appreciate your input. Thanks.

Asked By Ted Salyer | Aug 26 15
7 Answers

Skipping radiant floor heat in passive house.

I'm building a house with (conservative numbers) R 60 walls and R90 ceiling. The windows are in-swing casements with double seals. The floor is going to be stained concrete on 2" insulation. I had 2 consultants tell me that I will not need radiant floor heat it will be too much. We will have a whole house air circulation system and a gas fire place. I am worried about not putting in the pipes in the floor and then being wrong. I am considering just putting in the heated floor under the rooms away from the fire place. I could add a heater to my whole house ventilation system if needed.

Asked By Jenz Yoder | Aug 25 15
7 Answers

Does an 850-square-foot house have to have return air ducts?

I live on a slab one story home. I currently have an old forced air gas furnace that I would like to get replaced as well as install central air conditioning. I had a local contractor come out and quote a complete system and was told I would need all new ducts because I didn't have a return air system. The furnace currently is in a central closet with a large air grate on the side letting air back to the furnace. It is right in the middle of the house and I usually leave all doors to all bedrooms open. He quoted me $12000 for the whole job.

Asked By Brett Obraza | Aug 27 15
9 Answers

Wall stack up opinions - using rigid foam as air barrier between double stud wall?

Hi,

I'm in climate zone 6A looking to build a partition wall between an attic bonus room. One side of the bonus room will remain as cold storage, and the other side will be heated by minisplits and resistance backup. I'm looking at building a double 2x4 wall separated by rigid foam. The exterior wall would be framed 24" o.c. to maximize insulation. There will be no plumbing or wires in the exterior wall. The interior framed 2x4 wall will be framed 16" o.c. and will contain wiring, and will possibly be plumbed for a sink.

From cold to warm, here is what I'm proposing:

Asked By Rick Van Handel | Aug 24 15
7 Answers

Anyone familiar with Insultex house wrap?

I was wondering if anyone had any thoughts on this house wrap - http://www.insultexhousewrap.com/

They appear to be making some exaggerated claims and I am not certain that the R-value claimed would be possible.

Any thoughts?

Asked By Marcus Sheffer | Jul 31 15
3 Answers

Opinions sought on window details

Building a "good" house in zone-5.

Current plans are to use 2x4 framing with plywood sheathing, then two 1" layers of reclaimed foam, 1/2 thick furring for a rain screen and hardiboard siding.

I have a builder willing to do this and we are discussing window details. The windows are 5" thick and come with either an installation fin in the middle or no fin and you use straps to attach the windows.

Asked By Michael D | Aug 27 15
0 Answers

Basement cement floor as shower pan

Our planned basement shower pan is a 5' x 5' area of the poured concrete floor, sloped on all four sides to a central drain and sealed.

This isn't a normal request for a concrete contractor, I'm sure. Has anybody our there done it this way? Are we setting ourselves up for trouble?

(By the way, Plan B is to have the contractor drop the floor a couple of inches in this area and have the tile guy build a conventional mortar bed, Kerdi waterproofing and tile shower pan.)

Asked By Esther Streusand | Aug 27 15
4 Answers

My project is insulating a 54 x 72 x14 pole barn in southwest Michigan

My project is insulating a 54 x 72 x14 pole barn in southwest Michigan.

I was able to purchase 4' x16'x 2" EPS foam sheets with foil on one side for a very reasonable price, (small imperfections) from a near by manufacture. I installed it in the walls, foil side...

In the ceiling I installed the EPS in the 4' space between the trusses, foil side down facing the interior, it will be covered with the interior steel liner and 14" of blown in insulation will be above. The building has a concrete floor with drains. I plan to heat with LP gas (infrared tube heaters).

Asked By Michael Schumacher | Aug 27 15
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