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6 Answers

Choosing wall assembly details

Hey Advisors,

I'm asking this question for a neighbor. I have my theory but I would like to see what the general advises have to say.

Here's the building:

located in central VT

double stud wall construction, rough cut 2x4 construction, total wall thickness around 8"

sheathing is diagonal rough cut 1x6

2 stories, full first floor and knee walls on second story

cellulose as bulk insulation

The question:

In Green building techniques | Asked By David Burke | Oct 14 12
1 Answer

Put exterior wall on top of ICF foam?

I am building a wood building slab on grade in North Dakota. I poured ICF frost walls, keeping the wall down 3 inches from the top so that i can cut inside form down and pour the slab tot he outside form to prevent heat loss from radiant floor. If I put the wall flush to the outside of the slab, how do I deal with the 2 inch foam on the outside? Z flashing over it? A friend said he just put his 2X6 wall flush with the outside foam, so he has 3 1/2 inches on the slab and 2 inches on the foam. Is that a good idea? Not sure how to deal with this.

In General questions | Asked By Bob Paulson | Oct 15 12
9 Answers

Best way to insulate solar tube skylights?

We are remodeling an old DARK house with limited opportunity to add windows.
Plan was for 2 solar tubes in bathroom. Owners were so happy with additional light
we are adding more. What is best way to insulate tubes. The bottom 14" will be in the new cellulose attic insulation, but 2'-4' will be exposed above insulation.
Fiberglass batts and duct tape would work but be tough to do neatly with no gaps.
Any suggestions?

In Green building techniques | Asked By Richard Patterman | Oct 10 12
5 Answers

Are sealed electrical boxes needed for the airtight drywall approach when using drywall gaskets?

I'm planning to use the airtight drywall approach to air-sealing in a single room renovation.

As I understand it with internal walls the concern is penetration into the attic. So I'm using drywall gaskets from Conservation Technology to seal the drywall at the top (and bottom plates). If the top-plates are well sealed do I need to worry about air-sealing the electrical boxes? Warm air could penetrate but not rise into the attic (or more likely in Zone 2) warm air won't ever get from the attic behind the drywall to enter the room.

In Green building techniques | Asked By James Howison | Jul 20 12
1 Answer

ADA with fire sprinklers

Anyone here done airtight drywall with fire sprinklers in the ceilings? Build a foam box around each one?

Any tips or tricks?

In Energy efficiency and durability | Asked By Jack G. | Oct 14 12
1 Answer

Covering popcorn ceiling

We have a popcorn ceiling in our house with a cathedral ceiling. We would like to cover it with 2" foam insulation and sheet rock over the insulation. We only have a 4" of insulation above the current sheetrock and have a 2/12 pitch roof. Will this be a potential problem for condensation or mold?

In General questions | Asked By Jim Palmer | Oct 13 12
5 Answers

What is the safest insulation product for our 50-year-old home?

We are paying $300.00 a month during winter in our 3-bedroom home, and $250.00 in the summer with the air conditioning. It's ridiculous.

Any suggestions?

In General questions | Asked By juliet erb | Oct 12 12
7 Answers

Drainage for floating slab

We have a nearly level site with a layer of clay below about a foot of topsoil, such that we've measured water less than six inches below the surface in the Spring.

Where would you install drain pipes for a floating slab that has only 18 inches to work with (see drawing)? We were planning on installing a second set of drain pipes closer to the surface to take the gutter water. There is very little slope across the property so draining to daylight will be difficult. Do you think we need the double exterior drains?

In GBA Pro help | Asked By Elizabeth Kormos | Oct 11 12
1 Answer

What do you recommend for a crawl space vapor barrier?

Its surrounded by frost wall. Wood floor system 2' above. Will 6mil plastic do? How about fastening / sealing to concrete frost wall?

In Green products and materials | Asked By K Greenblott | Oct 11 12
8 Answers

What is the best way to superinsulate a walk-out basement?

I need an expert's opinion of my current and future game plan for my Upstate NY - Zone 6, 1968 back-split renovation.

Q1: Can I safely add 4" of exterior poly iso, since I will already have 3" of closed cell on the interior of the wall?

Q2: How can I improve this plan?

See plan details below.


In Green building techniques | Asked By Alwyn John | Sep 26 12
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