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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.

In General questions | 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.

In Energy efficiency and durability | 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.

In General questions | Asked By Rob Leonard | Sep 14 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.

In Energy efficiency and durability | 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.

In General questions | 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.

In Mechanicals | Asked By Daniel Griscom | Sep 15 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!

In General questions | 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)

In GBA Pro help | Asked By Jeff Conners | Sep 12 14
1 Answer

Roof insulation / decking combination

Hello, I live in Winnipeg MB, Canada (Zone 7, North of North Dakota).

I am insulating my garage ceiling to R22+ (standard pink fibreglass between 2x8 ceiling joists). I am also looking to insulate my garage roof to keep some of the heat from the summer out of the attic space in which I will store some things that i do not want subjected to high attic temperatures (I also expect this will help keep the garage cooler as well since the attic will be only about as hot as the outside air at most.

I intent to layer the system as follows:
1. OSB as the roof decking

In Energy efficiency and durability | Asked By Mike Gagne | Sep 14 14
5 Answers

Zone 4B - 2012 IBC and SHGC

The new 2012 IBC adoption in my future building area will mandate that windows can only have a maximum of 0.40 SHGC, including the south facing windows. I am trying to achieve a Passive House design but the low SHGC mandate makes it more difficult. I am going with Intus uPVC triple pane windows. Originally I was going to go with the 0.49 SHGC for the south elevation but now I have to go with the 0.37 SHGC. The building department will NOT budge on this factor and will not allow any windows > 0.40 SHGC.

In Building Code Questions | Asked By Peter L | Sep 13 14
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