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4 Answers

Sill slope? Sealant tape?

How much slope is recommended for window sills? The house isn't in an coastal or otherwise very exposed location, but isn't in an arid or especially sheltered place either.

I'm planning on using beveled siding, placed on a flat plywood window buck, to help move water away from the opening; the exterior face of the window frame will be set about 4 - 5" back from the outside of the exterior sheathing. I'm trying to figure out how much extra room (vertically) to include in the rough opening.

Asked By Graham Fisher | Sep 16 14
5 Answers

Air sealing question: Assistance requested for 6th side of building envelope

My husband and I are homeowners who are working on a very deep energy retrofit of our 1860's house, almost a total rebuild. We have learned so much from this website and the Q's and A's from everyone's contributions, so many thanks to all readers and contributors. We had already started the building process when we learned of this site, and are now attempting to make accommodations for deficits in our education and processes during the early stages of our build.

Asked By Howard Lederman | Sep 14 14
13 Answers

Retrofit heating system

We recently bought a second home in the Catskills, which was built in the 1930s. Current heat system is oil furnace forced air with a pretty new high end furnace. We had an energy audit done and found that the house was not well insulated at all and are in the process of takin advantage of energy efficiency programs to upgrade.

Asked By Carole Florman | Sep 15 14
4 Answers

Out-sulation vs Double Stud Walls

I was reading some old GBA discussions about double-stud wall designs and the added difficulty of keeping the sheathing dry (relative to wall designs that place appropriate amounts of insulation over the sheathing). This prompts me to wonder why the double-stud approach has its adherents when an out-sulation approach can be used to achieve the similar R-values and protect against thermal bridging while dispensing with the uncertainty regarding moisture. Besides being of general interest to me, I am hoping the responses will help me decide the 'best' way to proceed for a future project.

Asked By Rob Shuman | Sep 16 14
6 Answers

Raising a sunken floor

I am planning on leveling an 18” deep sunken living room (15 ft x 15 ft ) with the surrounding area and then install travertine flooring. To save some concrete, I am planning on using EPS to fill the first 14” of the sunken room and then poor a 4" thick concrete slab. I read an answer to a similar situation posted a few years ago that lead me to believe that the concrete slab my not be needed, and that I could possibly install plywood or hardy baker board on top of the foam with foam compatible adhesive.

Asked By Andres Ferro | Sep 5 14
1 Answer

Insulating and air-sealing a room-in-truss over a garage

Hello,
I am looking for some clarification on insulation and air-sealing, when dealing with room-in-truss construction for a conditioned space over a garage.
I live in Michigan, climate zone 5. I have a 28x36 garage, with 28ft span 8/12pitch "attic" trusses. the trusses have a 2x10 bottom chord and 2x8 top chords with 2x4's at the kneewall. I have a permanent stairwell going to the room in the truss, and I plan to heat the room. I have in-slab hydronic heating on the garage floor.

Asked By Ben Helmreich | Sep 15 14
15 Answers

Spray foam & wood roof deck

100 year old residence is located in Zone 5 w/i 50 ft of ocean/bay & has a 100 mph design wind load requirement. It is located high on a hill & completely exposed. Vented eave ridge is not advisable in this area do to high driven rains. The home will not be the primary residence, therefor optimal heating, venting & dehumidifying will not be maintained 24/7.

The energy code requires 49R roof assembly for the proposed occupied attic w/ cathedral ceiling. 49R requirements & existing 2x8 rafters, limits choice of insulation to closed cell spray foam.

Asked By Sheila Sullivan | Sep 12 14
11 Answers

I'm wondering if you can insulate the attic roof rafters

Thanks everyone for your insight. I think the thing I've learned is that if your not going to finish the attic area and the walls to the finished room are insulated you don't have to insulate the roof joist, but you do need to insulate in between the floor joist and the finished walls.

In our doormer, There are two small doors going into the attic area from a finished dormer area, and the walls that are finished have batting. The floor joist in the attic have old blown fiber glass that has settled, so we need to fluff it up or add to it.. Thanks so much everyone.

Asked By kristin burton | Sep 12 14
3 Answers

Is Thoroseal good for the capillary break on footing?

I'm looking for something that can be applied to green concrete (7 days after pour ok) that would provide the capillary break on top of the footing before the foundation wall is poured. Is Super Thoroseal (or regular Thoroseal or Thoroseal foundation coating) going to work?
Thanks!

Asked By e c | Sep 15 14
12 Answers

Insulation question for new house build

I’m building a brick bungalow in zone 5, please help critique my insulation. The sheathing is 1” Polyiso (foil faced) wrapped in Typar building wrap. I realize the polyiso should be thicker, but I’m told it’s too late. The walls are up and the windows are purchased.

Attic - R50 loosefill cellulose

Main Floor – R22 CC spray foam in 2x6 wall with no VB, drywall and latex paint
- The other option is R10 CC spray foam with R14 Roxul and no VB.

Rim Joist – R12 CC spray foam and R14 Roxul (thermal barrier required)

Asked By Jeff Conners | Sep 12 14
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