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3 Answers

What is the best method for insulating a crawlspace ceiling?

I have a vacation home in upstate NY, that has fiberglass batts in between the crawlspace ceiling joists. I want to remove the fiberglass and replace it with something less rodent friendly. The crawlspace floor and walls are encapsulated and the space is dry. Any suggestions?

Also should I spray foam the rim joist area?

In Energy efficiency and durability | Asked By David Jackson | Jan 29 13
13 Answers

Double Wall

I am planning on building a new house and am looking at using a double wall. Outside wall will be 2x6 studs on 16 centers with ½ plywood sheeting and rain screen. Roxul R24 in cavity’s. Inside wall I will use 2x4 on 16 centers. I will leave a 1 inch gap between both walls. Is this enough or two much? In the 2x4 wall cavities I will install Roxul R14. I have been doing some research hear on the internet and I have read that sometimes the 2x4 studs warp because of no sheeting on the opposite side of the drywall.

In Energy efficiency and durability | Asked By Sam Fowler | Jan 22 13
3 Answers

Protecting crawl space slab foam

We have a 4' crawl space that has eps foam+vapour retarder for a 'slab.' what are some cost-efficient options for protecting the foam and poly? i imagine the homeowner will want to use the space for some storage. p.s., concrete is not an option....thanks again, gba!

In General questions | Asked By erik olofsson | Jan 28 13
4 Answers

Foam sheathing

My whole house has been sheathed with OSB. My builder will be applying housewrap to this next week. I will have "innie" type windows installed as well. He will also be covering the housewrap and OSB with a layer of foam board. Since the housewrap is under the foam, is it necessary that he tape all foamboard seams? I would assume since the housewrap is under the foam, this would not be necessary?

In General questions | Asked By Aron Robinson | Jan 26 13
7 Answers

Wall section schematic help

I have a wall section scheme from an architect that has multiple vapor retarders and i'd like to value engineer it for energy and $savings- I think there is a lot of opportunity and am hoping for your input.

In General questions | Asked By Robert Post S.E. Pennsylvania Zone 4a | Jan 27 13
3 Answers

I want to add 2 inches of blue board to the addition I'm building. Will it cause moisture to build on the inside wall?

I live in central Maine on the coast. Some have warned the dew point will fall on the inside of the 2x6 wall and not dry out. Others have said it will dry out in the summertime if i use a breathable paint on the drywall so it can dry out that way.

My slab on the 1st floor is heated and insulated w/ blue board 2" on the sides and 4" on bottom. Please advise.

In Energy efficiency and durability | Asked By PERRY GREEN | Jan 26 13
1 Answer

High humidity in a tight building enclosure

2011 mid-rise wood frame apartment building with aluminum windows. There is evidence of high condensation. Windows have thermal breaks and IGU is per code.

There are units which have not required any heat at all this winter. Building finish is EIFS.

Where is the moisture coming from? What is the best way to deal with any condensation?

In General questions | Asked By Timothy Gooding | Jan 26 13
4 Answers

Dense-packed cellulose OK?

We built a home 11 years ago with 5 inches of Icynene sprayed against the 1/2-inch plywood sheathing, no vent, in our cathedral ceiling.

12 inch I-beam rafters from soffit to ridge, no vapor barrier.

After energy audit it was recommended to fill remaining 7 inches with dense-packed cellulose. Heat is a wood stove and radiant flooring, minisplit for AC and auxiliary heat.

We are in southern Wisconsin Zone5A/6B.

What are your thoughts?

Thank you in advance,

In Energy efficiency and durability | Asked By Scott Doherty | Jan 25 13
1 Answer

Improving windows on older brick house

We have a late 1800s brick house in the Midwest ( Zone 5A ) with original double hung weighted sash windows. The current configuration includes poor quality combination storm windows. I would like to improve the performance of the windows and am looking for advice about storm windows that would be appropriate for the appearance of the house. We live in a designated "historic district" so appearance from the street is important. I've considered interior "storm windows". What advice can you offer?

In Energy efficiency and durability | Asked By Jon Kilpatrick | Jan 26 13
1 Answer

What kind of tape should be used to seal the seams of foam board?

We are using XPS on a basement wall. I have heard of using foil tape or Tyvek tape but I have read these may not the appropriate choices. Some tapes can eat the foam or provide a permanent seal for years.

In Green building techniques | Asked By Tom Markowski | Jan 26 13
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