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7 Answers

Floor Slab: Is a Vapor Barrier Needed with Rigid Foam?

If one is using 3" of rigid foam (EPS) underneath a 4" slab-on-grade, does one still need to install a vapor barrier?

Here is the build-up from the ground up:

4" compacted AB
3" EPS (termite treated)
4" concrete

Asked By Peter L | Apr 18 15
13 Answers

Request for comments on this wall mock-up.

CZ 6B - SW Colorado - 7000'

Asked By Chuck Jensen | Apr 18 15
0 Answers

Densglass & Stucco

Can one apply EIFS or stucco directly to DenGlass or does one need to treat DensGlass like wood/OSB sheathing?

Can DensGlass be used on a soffit with it directly being applied to the OSB sheathing?

Asked By Peter L | Apr 19 15
3 Answers

Do I need to use concrete screws for plywood over an insulated floor?

i am following your advice on using XPS on concrete basement floor followed by two layers of 1/2 inch plywood. My concrete floor is 15 yrs old will I have trouble with concrete screws in older concrete? Can I just fasten the second layer to the first layer of plywood or can I use adhesive on the first layer or do I need the concrete screws?

Asked By Rita Erskine | Apr 17 15
4 Answers

Laying out mini-splits for a new home

I have a new home in the design stage and have been working with with my HVAC sub and the wholesaler to layout and locate mini-splits for the project. The house will be 2550 sq.ft. on a slab with R40 walls, R75 ceiling and very tight. We are in zone 5, floor plan is attached. We will be installing an ERV for fresh air.

The HVAC guy and the wholesaler want to put a head in each bedroom as well as the entry, office, family room and great room and run them off of 2 separate outdoor units. Their concern is to provide uniform temps throughout the house.

Asked By Terry | Apr 17 15
13 Answers

'Finishing' above-grade Roxul Comfortboard: What are the best practices?

I'm building a new home. The exterior of the home, from the bottom of the basement to the edge of the roofline, is covered in 2" Roxul Comfortboard.

Asked By Ryan Lazuka | Apr 14 15
7 Answers

Cathedral ceiling rebuild techniques?

I have 900 sq feet of cathedral ceiling. Zone 7b. Its 2x10 rafter construction. No venting with recessed lights. Mold and moisture remediation will begin in 2 weeks. I've been doing lots of reading on GBA, I love this site and forum. Right now, the rebuild plan is a sealed ceiling with 4" of 2lb spray foam with the remainder of the rafter bay filled with fiberglass batts. All recessed lights will be removed. I'm considering T&G for the interior finish. Will the T&G change my insulation plan? Am I missing anything?
Thanks.

Asked By Scott Buchanan | Apr 2 15
2 Answers

White pine

Hi, I'm needing to build a large rabbit hutch with an enclosed run, and I have to use white pine because the bunnies will chew on the wood and it is safe for them.

Some areas will be exposed to the weather and I can't paint it. How will white pine hold up unfinished?

Asked By Girene | Apr 17 15
1 Answer

Can isocyanurate paper/fiberglass faced insulation board be used on the inside of a wood stud framed wall?

Have old house with 4" cavity in wood framed walls. Exterior has 1" sheathing board with 6" wood shiplap siding over it. Can we put isocyanurate bd on interior of walls to increase the R-factor before we sheetrock top 4' and wood veneer the bottom 5' of the wall. Is their any increased fire hazard or other concerns

Asked By Bill OConnor | Apr 17 15
5 Answers

Do I need an interior vapor barrier of some sort?

The house was built in 1991 and is located in SE Mich, Zone 5?

It currently has a wood composite siding, no housewrap, and a mixture of plywood and double foil-faced foamboard (no discernible pattern). The studs are 1x4s. On the inside, it had fiberglass with a plastic vapor barrier. The windows are flangeless wood windows that I plan on keeping and restoring.

Asked By Hedy O | Apr 17 15
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