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12 Answers

Best method for air sealing an existing tongue-and-groove (wood) ceiling? Sheetrock is out.

The Home is located in Zone 4 NC. Question #1 Any problems using closed cell spray foam on any

large cracks , in attic at ceiling plane. Then using blown in cellulose ?

Question # 2

Any best method for securing tongue and groove ceiling to prevent cellulose from pushing down ceiling ? Netting etc.

Question # 3

Thought of using Reclaimed Commercial Roofing foam board Fiberglass faced , using cut and cobble

at attic joist bays. Leaving small air gap from tongue and groove ceiling. My thought was it would

Asked By Greenconfusion | Apr 13 17
0 Answers

Ventilation - Ridge Vent / Soffit / Gable

Zone 4 in NC (Raleigh)

Attic/3rd floor recently finished and the area has open cell spray foam from soffit vent to ridge vent. Prior to spraying the livable space, the foamed space had a gable vent (now sealed), ridge vents at all top points, and soffits throughout. There's another gable vent that is not sealed on the opposite end of the livable space/house with a much lower roof that I keep the access door closed (reachable thru mechanical room, that is foamed as well). I don't consider it part of the 3rd floor since it has a lower roofline / not livable (much duck down to walk).

Asked By bhsizemo11 | Jul 28 17
0 Answers

Trying not to over-ventilate attic with continuous soffit board?

CZ3, 2065 square foot vented attic. Simple gable (36x60). If I follow Joe's advice to split the net free vent area (1/300) to 60 or 65% at soffits and 40 or 35% at roof I'd be aiming to put approx 600 square inches on the two 60 foot sides (300 square inches per side). And then the remaining 400 square inches on the roof.

Asked By Inger Peters | Jul 28 17
3 Answers

Hardwood floor in basement on concrete - new house

I’m building a house in CT and I have a question for the forum.

In (under) my basement, I have virgin dirt, 12” of stone, 2-3” of spray foam insulation, then 4” of concrete slab. I am looking to put down ¾” hardwood flooring, and have been given different pieces of advice on what to do.

I was told that I could put down another vapor barrier (6 mil plastic) and then ¾” plywood nailed to the slab, and then the hardwood on top.

I’m worried that if I put the poly on top of the concrete, then I will create a moisture trap around the concrete.

What would you do?

Asked By MillerConstr | Jul 27 17
3 Answers

Choosing between Mitsu and Fujitsu mini split, need advice

I'm debating between two contractors. One sells mitsubishi mini splits and the other sells fujitsu

I'm heating a finished room over my garage which is about 750 sqft and has awful(!) insulation in the roof. The Fujitsu guy said that an 18K unit should suffice but I've plugged numbers into a sizing calculator and I'm pretty sure that I need a 24K unit (~26K BTU heating required per the online calculator I used)

Asked By maquino | Jul 27 17
4 Answers

Rigid foam over existing drywall?

I'm planning on converting half my garage to living space, and I would like to add three inches of rigid foam insulation and another layer of drywall over the existing drywall.

The walls are 2x4 on 16" centers with fiberglass batt insulation, plywood sheathing (or possibly OSB), house wrap, and vinyl cladding. Can you think of any reason why this technique might pose a problem in my northeastern climate?

Asked By Ben C. | Jul 27 17
0 Answers

Inadvertant trap in mini-split line set?

I'm finishing the installation of my mini split line sets and realized I may have introduce a "trap" into the line set due to the way I had to route it.

The main line set runs from the compressor to the branch box in the attic. From the branch box, the line sets run down into one stud bay, in a 180 degree bend, through a stud, and pointing back up into another stud bay. This 180 degree bend is my concern.

Asked By Mike M | Jul 28 17
4 Answers

Ceiling Vapor Barrier

I am in the process of building a 12 inch double stud wall assembly with dense pack cellulose insulation. I am planning on wrapping the inside wall with a smart vapor barrier of either Siga Majrex or Intello Plus. I have heard Siga's Majrex is a superior product in that Intello has had some issues with trapping moisture from fall months when the barrier is mostly open, due to the transition into winter when the perm rate shrinks and the water has not had enough time to transmit out of the wall cavity. (This is advice I received from a retailer of Siga so I am taking it with a grain of salt)

Asked By Chris Roche | Jul 27 17
1 Answer

I have just had a SIP panel building constructed and concerned about a bathroom tile install.

I have just had a SIP panel building constructed and concerned about a bathroom tile install.
Master shower tile wall will be attached to Durock. ...
Should I put air space between Durock and OSB SIP wall? or possibly ice and water? or should we just attach Durock to OSB ?

SIP panel company is EPS - They had no strong opinion.

Thank you - Howard from Sturbridge MA

Asked By Howard Kelley | Jul 28 17
3 Answers

How to insulate the 'attic' of a 4' x 14' bump-out with hip roof.

This 100 year old house will be getting exterior insulation (3" SPF is current plan). The attic was insulated with SPF with venting for the underside of the roof deck. Intend to tie-in the attic SPF with the wall SPF therefore the soffits were removed.

There are 3 bump-outs that could compromise the continuous layer of of SPF that we plan to add. The largest is 4x14 (exterior wall size) and has a hip roof. It is currently insulated with pink fiberglass; seen from the eves. Likely done 20+ years ago when the last shingles were installed.

Asked By TIM LANGE | Jul 27 17
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