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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.

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
2 Answers

Wish list for the big box stores

Recently a friend who works at Lowes (sponsor of the Builder 20 peer education program that has helped my business immeasurably) asked me a really thought provoking question.

"What do Green Builders wish we had on our shelves that we don't currently stock."

In Green products and materials | Asked By Michael Chandler | Apr 4 12
14 Answers

Does anyone have an appreciable history with installation of horizontal vinyl siding over furring strips, attached through several inches of rigid foam to studs?

I am referring to a general wall assembly with several inches of rigid foam over studs, followed by 1-by or ripped 3/4" ply furring strips attached with headlok screws into studs, say on 16 in. centers--so that there are voids, or vented, areas between strips. How does the siding installation hold up if installed over such strips? Is it good to make the strips wider than, say, 4 inches so the vented areas are less and support for the vinyl is more?

In Green building techniques | Asked By Sonny Chatum | Mar 29 12
11 Answers

Cedar shakes over foam

I am installing cedar shingles on a gable end wall over 1" Dow Styrofoam over Tyvek Drainwrap, over 7/16" OSB. Am I OK to attach the shingles directly against the foam with ring-shank siding nails through the OSB? Is there a better way? I am using premade "panels" of shingles on one gable end and single shingles on the other.
Thanks for any help and advice.

In Energy efficiency and durability | Asked By jpeaton | May 3 10
5 Answers

ERV airflow imbalances

Hey GBA,

Longtime-no-ask-question-to. I hope you are all well.

In Energy efficiency and durability | Asked By Art Vandelay, AIA/LEED AP+, Zone 5 | Apr 4 12
2 Answers

How to properly air seal and insulate a cathedral ceiling composed of structural T&G cedar

This is an existing roof structure currently experiencing moisture problems most likely due to air leakage. This roof is in Winnipeg, Manitoba Canada, a very cold climate. Right now it has approximately 4" of EPS foam and tarpaper. One of the primary reason to address this roof is that there has been significant carpenter ant activity over the last few years. Would air sealing with caulking on the inside be enough of an air seal? (the cedar is the interior finished ceiling as well).

In Energy efficiency and durability | Asked By Jon Fast | Apr 4 12
1 Answer

Foam insulation panels on stud walls inside or outside?

Most details show foam insulation panels added over plywood sheathing on the outside. This generates all kinds of detail problems with windows, flashing, and siding attachment. Yes they can be done. But can these new details be done right by a contractor who has never done it before,.
Why not use polyiso panels on the interior? Joints can be taped and sealed for air tightnes. Furring screwed thru as on some exterior details holds the drywall. I plan to use 3" or more.

In GBA Pro help | Asked By Roger Blaho | Apr 4 12
2 Answers

Attaching corner trim over rigid foam

I plan on re-siding, with 4" polyiso panels underneath. Question - I want to use corner trim on outside corners. I also really want the polyiso to overlap the corners - how do I attach the corner trim?
Not sure how to attach the corner trim if the polyiso overlaps the corners.

In Green building techniques | Asked By Timothy Holzmann | Apr 4 12
33 Answers

I am building a brick home in Houston.

Is this wall construction plan sound? I have a 5 1/2" brick ledge with the following plan: Brick -> Air Space -> Tyvek -> Osb -> 2" by 4" frame -> Blown Cellulose -> Dry Wall -> Paint. I am concerned about solar [vapor drive].

Home Details:
Location Houston
Ventillated Crawl Space
Ventillated Attic
Large 2nd floor space over driveway
Living area over detached garage
Brick Veneer
Asphalt Shingles
Cellulose Insulation

In GBA Pro help | Asked By Robert Cozart | Jan 18 10
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