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0 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
3 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
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
11 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
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
6 Answers

Options for air sealing T&G ceiling with no air barrier installed

Hello all,
I apologize if this question appears a repetitive one, as I have read through a good bit of the Q&As here, but still cannot determine my best course of action.

Asked By Rob Leonard | Sep 14 14
10 Answers

The differences between mass and insulation

The "I installed more attic insulation and now my AC runs more" thread got me thinking about the mass effect a bit.

Asked By Nathaniel G | 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
10 Answers

Should my indirect hot water heater have a mixing valve?

I have a 2300 square foot colonial, built 1960 in Massachusetts (Zone 5A), with three zones of fin tube baseboard. There's a 75 gallon whirlpool tub which we almost never use; the two showers are fairly low-flow. Heat loss done by Comfort-Calc.net was 55,840. I use town water, which is very good quality (Quabbin reservoir). I've accepted a bid to replace my heating system with a Lochinvar WHN-85 boiler and SIT40 indirect water heater.

Asked By Daniel Griscom | Sep 15 14
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