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13 Answers

Still trying to understand why you don't care about trapping vapor under a vapor barrier

Still trying to understand why you don't care about trapping vapor under a vapor barrier if there is vapor constantly pushing up from the earth. Also interested in good sealant.

In General questions | Asked By Chris Campbell | Feb 20 14
2 Answers

Waterproofing slab to wood sill?

Good Morning!

In General questions | Asked By Jon Weinrich | Feb 27 14
0 Answers

Resources on Klingenberg/ TJI Larsen truss construction?

We're looking at an addition/retrofit, exterior insulation. Trying to price out a few methods, including DPC. Does anyone know of a guide/resource/method that has been OK'd by either an engineer or i-joist manufacturer? I don't think the loads are significant, but they are being added in directions that I assume the i-joists weren't designed to handle.

In Energy efficiency and durability | Asked By Dan Kolbert | Feb 27 14
10 Answers

Wall assembly advice?

Curious what people think of the following wall assembly:

- 1/2 drywall w/ vapour barrier primer (also ADA).
- 2x6 wood frame wall w/ roxul or dense-pack cellulose.
- SONOclimat R6 structural fiberboard w/ Neopor EPS.
- Delta-Dry rainscreen.
- Horizontal 1x3 strapping @ 24" O.C.
- Combination of vertical wood lap siding and pre-finished metal siding.

Zone 6 build in interior British Columbia, Canada... area is a designated a temperate inland rainforest.

Thanks in advance!

In General questions | Asked By Daryl Ross | Feb 23 14
16 Answers

Add batts above ceiling to Icynene on roof deck?

We had our attic treated with 5 -6 inches of Icynene (an open-cell foam product). The team vacuumed out the very aged blown in cellulose that was in the attic.

While we have seen our bills go down, I am wondering if we might be even more comfortable with some simple rolls of fiberglass insulation added between the ceiling joists. Even though our bills have gone down, I hate the thought of sending heat up into the attic.

Opinions? Thank you for your time :)

In Energy efficiency and durability | Asked By Rachel Stutsman | Feb 24 14
8 Answers

Point source ERV (or HRV) and mixing

In my home, the whole basement has been renovated from a leaky post ww2 bungalow(Southern Ontario), making it much tighter than it used to be. The ventilation on the main floor is and has always been old, leaky and sufficient, but it is the basement where IAQ needs improvement.

With a forced air HVAC, Dr. Lstibrek says that mixing occurs anyway in supply/exhaust and balanced systems in this great article (if i read this correctly):
http://www.greenbuildingadvisor.com/blogs/dept/building-science/intervie....

In Mechanicals | Asked By cory b | Feb 24 14
4 Answers

Best approach to deep energy retrofit the stud bays in a brick home?

I have a three-story brick home in climate zone 5 with interior plaster walls on both wood and metal lathe-at least 2 inch thick in many areas based on prior renovation of a bedroom. Home was built in 1920 without stud bay insulation.

In Energy efficiency and durability | Asked By W. Timothy Ward | Feb 23 14
4 Answers

Thoughts on PERSIST construction in Chattanooga, zone 4a

I'm designing my home using the PERSIST technique and would like input on insulation ratios that are suitable for my climate zone. I'm in Chattanooga, climate zone 4a, with 3587 heating degree days and 1544 cooling degree days.
Practically speaking, we have 3 months of trying to stay warm, and 8 months of desperately trying to stay cool.
My plan is a 1200 square foot, 2 story, flat-roofed house with a simple footprint, oriented for passive heating, windows placed accordingly.

In Green building techniques | Asked By Myles Freeman | Feb 25 14
6 Answers

Strapping for dense pack cellulose

Looking for recommendations on the correct strapping spacing (12" or 16") to help prevent bulging with a dense pack cellulose installation on walls. We will be using Insulweb over 8" cavities, 16" on center framing.

In GBA Pro help | Asked By jessie pratt | Feb 25 14
4 Answers

Where are commercially available VIG windows? Are they vaporware?

When I first read about vacuum-insulated glazing (VIG) several years ago, I got really excited; R-10+ windows!! I've been checking every couple of months since to see if they were commercially available and they STILL don't appear to be.

I've got my 100+ year old home almost up to passive house standards with air sealing/insulation. The foreclosed-upon house flippers that we bought our home from installed the cheapest builders grade dual pane windows they could. These are the weakest link in our home's energy efficency.

In Green products and materials | Asked By David D | Dec 12 13
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