Q&A: A Forum for Green Building Experts and Beginners

[Click map to enlarge]

Please register for a free account or sign in to ask and answer green building questions.

The usual rules of courtesy apply:
1. Be nice.
2. If you can't be nice, be polite.
3. If you can't be nice or polite — well, please be brief.

To attach a photo or illustration:
Under the box labeled "More explanation," look for the words "File attachments."
Click that, and you should be able to attach a photo.

Thanks for joining the conversation!


11 Answers

Wood Flooring Over Concrete

I'm building my own house, its on a monolithic slab with 2" foam underneath and around the perimeter. My plan was to install strapping and then 3/4 plywood and then hardwood flooring. I was wondering if there were any possible flaws with this design or better approaches.

In General questions | Asked By Mark Hinkley | Mar 13 12
1 Answer

Do You Need to Tape & Seam Seal XPS Over 6 Mil Poly in Basement?

Hi everyone,

I had a question. I live in NJ zone 4. My basement is 4 feet underground and 4 feet above. I am doing an XPS reto install on the interior walls. I put down a 6 mil poly (5 inches up on all walls) and then 2 inches of XPS on the floor and lower walls. I have been using Dow Spray foam inbetween the wall of XPS and the XPS on the floor.

Do I need to seam seal all the joints using Tyvek tape (both wall and floor)? Or does the 6 mill poly below the floor eliminate the need to seam seal?

In General questions | Asked By Dan Nospa | Apr 10 12
4 Answers

Are wood headers insulated with rigid XPS as the filler as structurally sound as those padded out with OSB or plywood?

What about 2x6 walls with 2.5" of XPS in between?

In Green building techniques | Asked By Matt Black | Apr 9 12
6 Answers

Advice for lack of rainscreen or proper flashing

I'm hoping to get some advice regarding my split entry house (circa 1990) in Eastern Canada that has no house wrap, tape or sealant of any kind. Wall assembly is (inside to out) 1/2" GWB, poly v.b., 2x6 studs, 5/8" OSB, 1/2" EPS rigid foam (nailed with roofing nails and no tape anywhere), vinyl siding (no furring). The brickmould for the windows and doors rest against the insulation and are only flashed at the top, tied back to the insulation, not the OSB. I've been replacing windows as needed over the last 5 years and have noticed damage to the OSB and under the windows at each location.

In Energy efficiency and durability | Asked By Darcy Grant | Apr 5 12
6 Answers

Why is my vinyl siding melting on the side of my house?

The north side of my house is approx 20 yards from a neighboring house which has a 2nd story window. Vinyl is warped and has a melting appearance behind the outside HVAC unit.

The chimney for the pre-fab propane fireplace is also in this area and some of the vinyl on the built in chimney is warped. There is a seldom used blacktop parking pad between the two houses which is approximately 3 to 5 feet from my house.

Could the damage be caused by a sun reflection from the neighboring house and what can be done to prevent it from my side?

In General questions | Asked By Daniel Peck | Mar 30 12
1 Answer

BlueskinVP

Anybody have experience with Henry BlueskinVP? It's a fully adhered WRB and air barrier, but is permeable at 29 perms.

A cursory internet price check reveals it is in the $.50/sq ft range.

Martin mentioned it in Sept, 2010:
http://www.greenbuildingadvisor.com/blogs/dept/musings/new-green-buildin...

Just wondering if anybody has used it and had comments?

In Green products and materials | Asked By Bill Costain | Apr 6 12
18 Answers

HRV vs. ERV vs. Dehumidifier - Unique Situation!

Hi everyone. New member and first-time poser of question. :) Please keep in mind this is FAR from my area of expertise, so talk to me like a dummy; I won't be offended!

I live in Central-Northeast WI, so our annual temps run from about -40 to 90+
depending on the season. The summers overall I'd say are mild, while the
winters are colder than I'd like. :)

I run a home-based business breeding fish and propagating coral and as such,
have a pretty high humidity level (under 90% is pretty rare). I had been
running a dehumidifier in the past but it's recently died on me so it needs

In General questions | Asked By Fred Bocskor | Dec 1 11
2 Answers

Nanawall or La Cantina Folding doors and blower door performance?

I am curious if anyone has experience with blower door performance on a Nanawall or La Cantina folding door system (not as isolated elements, but rather impact, whether good or bad, on whole house blower door performance). I am a builder in Seattle area getting ready to start a new construction project with a number of great energy features including SIP wall and roof assemblies.

In Energy efficiency and durability | Asked By Greg Kruse | Apr 5 12
5 Answers

Using pressure treated plywood on exterior of carriage doors

After reading the article on building carriage doors I would like to build some using that technique but would like a less fancy / expensive approach. There would not be any window required. Could I use ½ inch pressure treat plywood that would be sealed and stained? This would eliminate the meranti trim and cap. It would also be much easier to construct. I am not concerned with insulation as the garage is not heated.
Thanks
Jay

In General questions | Asked By jay mcdonald | Apr 6 12
6 Answers

Closed-cell foam in stud cavities and Tuff-R on sheathing. This going to be a vapor barrier problem.

While residing my house I was planning on using Tuff-R over sheathing. Then in the next year or two I was going to spray closed-cell foam in the stud cavities later on. Or should I go open cell so moisture doesn't get locked in?

In Energy efficiency and durability | Asked By Michael Strid | Apr 5 12
Register for a free account and join the conversation


Get a free account and join the conversation!
Become a GBA PRO!