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3 Answers

Finding an Architect

I'm looking for an architect to design a "pretty good" simple 2-3 BR house of about 1100 SF in Orange County NY. There are some site challenges but nothing major. How should I go about finding someone aligned with GBA objectives?

Asked By Zenterman | Jun 17 17
5 Answers

Polyurethane caulk for bottom plate to slab sealing

I've been reading the various posts on bottom plate air sealing on this site. I'd like to avoid the expense of EPDM or Denarco sill seal. I'm wondering if laying down a healthy bead of a polyurethane caulk on top of the foundation wall prior to tipping up the walls will produce an adequate seal? In addition, the bottom plate would have the standard contractor 1/4 inch foam seal. Your thoughts appreciated.

Asked By Steve Wolfe | May 5 17
12 Answers

Caulk/adhesive for exterior sheathing to top and bottom plate

I've got my box of EPDM gasket for the bottom sill to foundation wall seal. Now for the exterior sheathing. I want to seal the top and bottom plates to the sheathing. Is it necessary to use a caulk that won't harden over time, or is construction adhesive OK? I'm planning to tape all the other exterior sheathing seams with Vycor Plus. Also looking for a recommendation on foam to use for any other penetrations to the exterior sheathing. Thanks.

Asked By Steve Wolfe | Jun 4 17
10 Answers

XPS and faced fiberglass

Hi all,

I am currently finishing my basement (6 feet below grade with 3 feet above grade), cylinder block walls. My contractor has installed XPS foam board 1" behind his 2x4 wall and hasn't taped the seams. He also is putting faced fiberglass in the cavities. I have painted the interior with water proof paint, 2 coats prior to the work starting.

cylinder block > water proof pain > 1" XPS, > fiberglass > drywall

Asked By Matt Duffey | Jun 12 17
22 Answers

Home is heating up in late evening

We live in a rather energy efficient 5 year old, two story, east/west oriented home. HERS rating, iirc, is in the 40s.

In the summer, the central a/c can maintain a temp of 72F most of the day even when outside temps go up to 95F. But in the late afternoon, just as the sun goes low in the sky, the a/c cannot maintain that temp and it will rise to anywhere from 76 to 79 on the upper floor. The a/c runs pretty much constantly during the afternoons.

I'm perplexed. What is causing this? Any suggestions to mitigate it?

Asked By Cedyathome | Jun 11 17
2 Answers

Spraying vapor barrier paint on open-cell foam


I want to use open-cell foam on a new project and am trying to meet the IRC guidelines. The insulation installer suggests spraying vapor barrier paint directly on the foam. I have read previous research on GBA that found this ineffective. However, would it also be detrimental to the performance of the foam, or would it make no difference?



Asked By user-6868809 | Jun 16 17
11 Answers

Used 3" Rigid Polyiso Insulation


Had a quick question regarding used polyisocyanurate . I have an opportunity to purchase 3" X 4' x 8' sheets that are reclaimed and 4 years old, they are paper faced on both sides.

The plan is to have 2x4 wall with 2 layers of the 3" polyiso on the outside (6" total) . All above ground.

Is there any reason I cannot use them for my exterior wall insulation?

Any issues with used Polyiso? or paper faced?


Asked By Dave B | Jun 9 17
1 Answer

Vented metal roof and underlayment

Hi Martin,

We're planning on installing a metal standing seam metal roof over an existing vented cathedral ceiling. In zone 5, the existing conditions to remain are gyp. board ceiling and fiberglass batt insulation between the rafters.

After removing the existing cedar roof and skip sheathing the contractor installed plywood and an impermeable (less than .02) high temperature self-adhered membrane over the whole roof.

Will the impermeable membrane create a situation where the plywood can't dry out?

Please confirm we should still vent the assembly at the soffit and ridge.

Asked By S G | Jun 16 17
2 Answers

Why is the "Green Homes" section blank?

When I click on section tab at the top, the page that I'm directed to is blank!

Asked By Cm Mm | Jun 15 17
8 Answers

Cathedral ceiling insulated with batts?

We finally received quotes back to insulate our cathedral ceilings the way I thought was best after a lot of reading on this forum. It is insanely expensive.....Just to preface-I wanted to use continuous baffles with dense packed cellulose/fiberglass. I was trying to limit spray foam in my house not only due to cost but other factors....

Asked By user-6816910 | Jun 13 17
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