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11 Answers

Best Material to go above T&G under SIP roof panels

This is a follow up question from this discussion


I have shingles and I need to know the proper material to go under the sip above the t&G and the best tape for sealing this material. There was no definitive answer given for the best product in this discussion. Also while it was covered for metal roofs, I need to know what is the best material to to go under the shingles and above the sip.

In General questions | Asked By mike kasmeier | Aug 1 12
8 Answers

Rainscreen performance during wildfires

I have started to work with some of the homeowners who were affected by the recent Colorado wild fires. To that end, I am putting together a presentation to begin to explain to local homeowners how to rebuild in order to best resist future fires. The presentation will highlight how many sustainable construction techniques for improved energy performance and durability also have benefits for wild fire resistance.

In General questions | Asked By taylor webb | Jul 31 12
5 Answers

Is a vented rainscreen needed for fiber-cement shingles in DC?

I'm looking at a residing project in Washington DC in which the existing wood lap siding is to be covered in fiber-cement shingles. The house was built in 1923 and the plaster walls have blown-in cellulose.
How crucial is it that a vented rainscreen be used? The additional cost is the issue. Housewrap is planned.



In Green building techniques | Asked By Rick Ruggles | Aug 2 12
0 Answers

Air barriers.....

I am considering using Siga Majvest as an exterior air barrier. Can any one tell me how this compares with the typical US approach of Tyvek in real work, work site conditions.


In Green products and materials | Asked By Bruce Friedman | Aug 2 12
2 Answers

MemBrain: does it do what it claims?

I am building my new home with a R 45 wall set up.
R24 blow in and R21 of exterior foam (4 inches)

I have read lots about the risks of interior poly. I found some information from this site leading me to a product called MEM-Brain by certain-teed.

I understand the principle behind the product, what I am questioning is the permability of the drywall that is covering the product with a couple of coats of paint.

Can the wall really dry to the interor with the MEM-Brain and a layer of drywall? Especially after it's been painted serveral times, say 10 years down the road?

In General questions | Asked By Brian Krmpotic | Aug 2 12
14 Answers

Deep energy retrofit planning

Hello all,

First off just joined the site and am very grateful for all the info you've accumulated here!!

In Green building techniques | Asked By Micah Fay | Jul 4 12
3 Answers

Open-cell versus closed-cell spray foam

My house is 7 years old, it's all crawl space underneath the house. They sprayed open-cell instead of closed-cell, which I did not know.

They did a good job, but i was told by heating guys a few years ago that i should take it out and put closed cell. My hardwood floors are cupping just a bit, not much, in certain areas.

Is it OK to have open cell? I'm going to sell my home in a few months and will that affect the sale? Or is it OK?

maria brittis

In General questions | Asked By maria brittis | Aug 2 12
3 Answers

Would plaster in a vented, unconditioned attic be an issue?

I have a friend who is putting a new roof on an 80-year old house in Pittsburgh. She's experienced problems with ice damming in the past and is considering adding a ridge vent along with the new roof. The attic is finished with a hardwood floor and plaster/lath ceiling. They recently added insulation in the attic floor.

Would the plaster need to be removed if a ridge vent were added?

In Green building techniques | Asked By Stephen Horvath | Aug 1 12
6 Answers

What is the best practice and material to insulate my crawspace ceiling?

I own a 22'X32' ranch home(vacation property) in upstate New York. I had the crawlspace "encapsulated" last year which took care of the bulk of the moisture problems. I'm left with fiberglass batts in the ceiling(floor of the living space) that are starting to fall and make a general mess of the space. Is closed cell spray foam a good option to fix this problem? What other issues might I encounter? What about rodents? They try to move in every fall, but I've been able to keep them at bay with prudent use of traps.

In Energy efficiency and durability | Asked By David Jackson | Aug 1 12
2 Answers

Can the DOW product Perimate be used as an exterior foam insulation and rainscreen in one?

DOW has a Styrofoam product called Perimate, it is a foam sheathing that is typically used in exterior foundation applications in which dovetail grooves allow water to channel out. http://building.dow.com/na/en/products/insulation/perimate.htm. Could this product be used as an exterior sheathing and rain screening in one product? I would apply bug screen at the bottom and use corravent s-400 underneath the freeze board to allow for some air to travel behind the siding.

In GBA Pro help | Asked By Jason Macdonald | Aug 1 12
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