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1 Answer

GBA slow?

Has anyone else noticed that since the recent maintenance, this site is extremely slow?

Asked By stephen sheehy | Apr 25 18
4 Answers

Is this a vapor-permeable air barrier?

1960's home... wall construction is as shown, with face brick on the back side. Silver faced material is thin (maybe 1/8" thick).

I did not notice originally, but in good light, once can see what may be perforations in the surface.

Does anyone recognize if this is a vapor permeable sheathing material?

Asked By Rossn1 | Apr 21 18
15 Answers

Painting old wood siding?

I'm looking to remove the vinyl siding from my house and either paint the old wood clapboard siding or remove it and replace with it LP, Hardie, or cedar - or maybe Boral polyash. Still doing the research on which siding to use. I've removed a small section of vinyl and the old siding is in pretty good shape but I've been told I'll regret leaving the old wood because paint will never stick to it. Blown in cellulose has been installed directly behind the clapboards and I've heard that also reduces the life of the paint. Thoughts?

Asked By Michael Mohr | Nov 28 17
3 Answers

Vinyl siding over Zip system

If you intend on installing vinyl siding over zip system, should you be using galvanized or stainless fasteners to install the zip sheathing? I am at a point of starting sheathing with zip system on a new build and would rather not install a WRB though I am concerned that using bright nails will rust and maybe eventually make its way onto the siding. Has anyone dealt with this in the past? Any thoughts or advice would be appreciated.

Asked By Brian Ducharme | Apr 23 18
2 Answers

Crawl space: To vent or not to vent?

Building here in Chattanooga (CZ-4), there is possiblity of a basement due to shallow soil before bedrock. And we're on a slope, so crawlspace it is.

I've been preparing myself for a conditioned crawlspace but have run across info from 475 that is making me question. If the underside of batt insulation is sealed with a product like one of their Solitex Mento products, airtight yet vapor open, would this be an alternative to sealing the entire space? Thoughts?

Asked By Ytsehoos | Apr 23 18
13 Answers

Rafter insulation - design

Hi all,

So am revisiting insulating my attic rafters. I am in Richmond Va and have a 2 year old roof. I debated spray foam (closed) but it is very expensive. So I am looking at doing a 1 inch air gap soffitt to ridge and using Roxul R30.
I will have to fur out my 2x8s for this to work.
My plan is as follows:
R-30 Roxul - allowed by my building inspector - 7.25" thick
Ripping a 2x4 in half - gives me 1.75" of depth for furring out the 2x8
To ensure the correct depth, rip some 2x4s to 1" high and 1/2" wide and nail them to the rafters along roof line.

Asked By Joe Watson | Apr 8 18
3 Answers

Basic vapor barriers question (kneewalls)

I've been reading GBA on air barriers.

Basic building science question that I'm hoping you can help me understand:

From a vapor/moisture perspective (ie, ignoring the 2x thermal barrier), what are risks to hanging polyiso on kneewall AND on roofline in a kneewall space? How much airflow is needed to reduce those risks of 2x vapor barrier?


Asked By Emerson | Apr 20 18
30 Answers

Are "Energy Nerds" in agreement on this?

"PV's are cheap enough now to remove the need to super insulated houses"

Asked By tech1234 | Apr 19 18
23 Answers

Insulating kneewall slopes from above

Unfortunately we are having to fix some poor quality work by insulation contractors.

How should we build baffles, or what kind of baffles/vents should we buy, to maintain >1” vent for 5’ sloped ceilings above a kneewall, which can only be accessed from the top attic?

Asked By Emerson | Apr 17 18
1 Answer

2 or 3 Coat Traditional Stucco Application with Drain Cavity

Mineral wool outside insulation is becoming more common in residential in my location. I favour this over rigid insulation by far for many reasons, but I'm trying to figure out a best approach for traditional stucco applications.

Asked By DarrenKC | Apr 19 18
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