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2 Answers

Pine Beetle kill plywood as air barrier?

We are using our sheathing as the air barrier and my partner is concerned that quite a bit of the plywood sheathing is compromised because it is made from beetle killed pine. Holes are visible on the surfaces, but of course we can't see right through to the other side. Anyone have any thoughts on this? Should we be concerned?

In GBA Pro help | Asked By jessie pratt | Dec 7 13
11 Answers

Cold sheathing: condensation & mold?

I have read most of the other threads on this topic--and would like to complement Martin and others who have provided great, detailed answers with patience!

My situation is similar but slightly different and I would appreciate some assistance:

  • Home in the hills of Seattle, WA (elevation 800 ft, so colder winters than typical for Seattle metro area)
  • Built in 1998. From outside-in the building envelope is natural wood siding (cedar/doug fir?), tar paper, 5/8" OSB, 2x6 wood studs, R19 fiberglass. Solid slab foundation.
In General questions | Asked By Brian Lent | Dec 4 13
2 Answers

What to do with tongue & groove sheathing, cavity insulation, etc?


Many thanks for your excellent website!!! It's been a big help!

I own a house built in 1953 about 10 miles north of Jay Peak in southern Quebec, elevation 715 feet, zone 6 / 7.

In General questions | Asked By Thomas Chaplin | Dec 5 13
11 Answers

Roofing material over sheathing which can't dry to the inside?

Underside of roof sheathing has polyurethane foam on it, so if it were to get wet, there would be no drying to the inside. Would it be problematic installing asphalt shingles on this roof? Thanks!

In General questions | Asked By Eric Mikkelsen | May 28 13
6 Answers

Cut and Cobble with Damaged ICF Blocks

The recent severe weather in the Midwest (I'm in central Illinois, climate zone 5A) left me with A LOT of damaged ICF blocks that were intended to be used for my foundation walls. Most of it is unusable (without significant bracing) due to the "lego nubs" being broken off or large chunks from the corners missing or one side of the block is broken but the other side is just fine. (The wind picked up the bundles of blocks, broke them up, and blew the blocks across a corn field...I'm still picking up little bits of EPS).

In General questions | Asked By Robert Kohaus | Dec 3 13
17 Answers

Condensation on foil-faced polyiso panels?

I stacked a bunch of 2" thick foil-faced polyiso insulation boards in the basement of our house, to prep for a major remodeling project. I returned a week later and noticed a puddle of water under the polyiso boards. (This happened in June, in a house along the shore in Massachusetts. The weather was humid, as usual.)

"Oh, no! A water leak!", was my first thought. I examined all of the copper pipes, looking for the leak. No luck.

In General questions | Asked By Mark Hays | Nov 27 13
2 Answers

Rigid foam exterior, spray foam interior rot problems?

My friend is building a small house in Vermont. He has framed 2x4 walls with exterior plywood sheathing and 1" of blue board outside of that. The facade will be stone with an air space behind of 1". He is planning on using spray foam to fill in the stud bays. I am more familiar with building materials than he is, and this plan struck me as questionable. Will there be rot problems with the sheathing in between the two foam layers? Should he use open or closed cell foam or a different material all together? He needs the R value of closed cell, but open cell has the ability to dry.

In Energy efficiency and durability | Asked By rye matthews | Dec 5 13
6 Answers

How to Insulate my Ceiling / roof deck

I have a pole building with metal siding, wood framing. The ceiling/roof currently has 2" vinyl backed fiberglass blanket insulation. I want to increase the insulation value of the roof without putting in an actual ceiling if possible. I don't think my trusses are engineered for a ceiling. and they are spaced way far apart. There is NO eve vents or any vents. If I need to vent I would lean more towards gable vents as I have no eve overhang to work with so would have to re roof all together. The goal here is to do this correctly with as little cost as possible and still keeping it simple.

In General questions | Asked By Kelsey Thomas | Dec 3 13
6 Answers

Fastening vertical pine lap siding over rainscreen — horizontal nailers?

I am having a hard time satisfying all our intentions in this scenario and would appreciate some timely advice.(ASAP :) If there are some available drawn details to point me to that would be much appreciated. We are are in climate zone 5A.

2x6 Wall
5.5" of Icynene insulation, will be sprayed in.
7/16 Zip wall sheathing
Tyvek - (taped with the small folds. We think its useless and have nicknamed it 'wrinklewrap')
Marvin aluminum clad windows.

Assuming we want the windows nailing fin on-top of but taped/lapped to the WRB.

In GBA Pro help | Asked By Arthur Jackson | Dec 4 13
3 Answers

I am remodeling my basement and planning on using closed-cell spray foam

I am remodeling my basement and planning on using closed-cell spray foam. I am also doing an earthquake retrofit. When/how should I install the spray foam?

I have a cripple wall and am required to install plywood to create a shear wall. My question is when/how should I install the spray foam? Should I spray before I install the plywood? Or after? Or both? My concern with spraying before is that the plywood needs to be nailed directly to the studs/bottom plate/top plate in the cripple wall so these can't be spray foamed so I am afraid this leaves a thermal bridge.

In Energy efficiency and durability | Asked By Lars Nystrom, | Dec 5 13
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