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4 Answers

Venting under standing seam?

I’m in the design phase of a ranch home (my own), 5:12 hip roof, in zone 3, mixed/humid region of the U.S. Since the attic will be used for HVAC, the plan is for it to be unvented. Initially, the roof construction was to be: plywood deck (taped), tarpaper, two staggered layers of ¾ inch polyiso, 2X sleepers laid on a diagonal for venting and a standing seam metal roof.

In Energy efficiency and durability | Asked By Tim Ellison | Aug 3 12
1 Answer


In zone 6/5, attached barn from late 1800's. Timber frame, true 2x3, boards, lap, and then vinyl (I didn't do it). Someone raised it and poured a concrete foundation. Leaving the ceiling / roof out of the equation for now.

Ceiling height code will be a stinker if I build up the floor much so... floating floor (2x4 grid with XPS) over poly barrier. Don't feel like it's enough at the wall edges, concrete "sucking" out the heat Playing with raising the sub floor near the exterior walls, sort like a built in ledge / kick plate, for some layer foil panels. Sounds strange but it'll look nice.

In Energy efficiency and durability | Asked By T Stills | Aug 4 12
11 Answers

Moisture challenges in my basement

My home was built in 1996. Split level, 1040 square feet. No central air or air conditioning.

We have always had moisture issues with our basement. Cool in the basement, on hot days, just as hot upstairs.

Our bedrooms are in the basement, the basement is completely finished however the floor is cement. We thought we sealed it years ago, but apparently not.

We try to control humidity with a dehumidifier however its not economical nor does it work well.

In General questions | Asked By christine hanek | Jul 30 12
3 Answers

Research info on heat wasted evaporating inside water?

I'm wondering if any has come across research documents or done their own research on how much heat goes into evaporating water that's inside, and ultimately whether or not it is a large or small amount of losses. I know of a building with a wash bay that is heated with modines, and am wondering how much of the heat used is attributed to evaporating un-drained water. Maybe there is a way to eliminate the excess water in a more cost effective manner, prior to its next use.

In Mechanicals | Asked By Mike LaCrosse | Aug 2 12
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
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