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24 Answers

Quarter Round on Rammed Earth

I'm trying to attach 3/4 x 3/4 to rammed earth pony walls I put in this rehab I am doing but the 3" finish nails are not holding. Any ideas?

I could try dipping in contact cement but I want to keep it all natural. What would they use for concrete?

Reason is although I used a surface sealer I found out the vacuum will tear the wall up.

PIC below is before, I'm pretty happy with it for my first project indoors. Realtor is going to give me feed back before I build homes.

Asked By Terry Lee | Dec 18 14
0 Answers

Polyiso for basement

Morning all

I am about to embark on the basement insulation. I have a question about polyiso. After much reading I was so sure about putting xps 2" rigid foam against walls and rim joist.

I read the gba, several other forums and as I understand, the steps are - clean the basement walls, clean rim joist, place rigid foam, seal with great stuff, place xps with foam glue on walls, tape the seams, seal the edges with great stuff, leave a inch gap and frame with stud walls.

Asked By sr kod | Dec 20 14
17 Answers

Sealing bottom plate to slab

My framer says that Sill Seal does not do a good job. I am inclined to agree with him. He is recommending a bead of liquid nails. I have been looking for real information. Certainly by now there have been some test run to measure the efficacy of various products and methods. And a new home slab is not a laboratory. How well does this or another product stick to a slab that has been wet and muddy?

Asked By Hugh Stearns | Aug 28 13
3 Answers

Insulating a floor above a garage

So this is happening more and more in my office now where we are designing townhomes with a garage below the living space and now that we are building these units in a cold climate I am beginning to have greater issues with it due to the plumbing that needs to run through the floor cavity that is above the garage.

Asked By Joshua Lloyd | Dec 9 14
6 Answers

Rigid insulation on exterior walls with high interior humidity

I built an addition on my house that includes a solar thermal array on the roof that heats an endless pool in the addition. The existing house is brick, so when i poured the foundation (foam blocks), i included a 4" brickledge. i have not finished the exterior yet, and am rethinking my options. I am in zone 6b. The construction is 1/2" sheetrock over conventional (not staggered) 2x6 studs with faced fiberglass bats in the stud cavities. exterior sheathing is 7/16" osb. finally, tyvek house wrap.

Asked By norm rostocki | May 25 12
9 Answers

Ceiling air / vapor barrier... Is this a bad idea?

I'm still struggling with my ceiling air / vapor seal challenge. I'm adding R50 cellulose above my upstairs ceiling. I'm also trying to get the house air and vapor tight. In Minneapolis it's always either way too dry in winter or too humid in the summer.

Asked By Ryan Griffin | Dec 4 14
1 Answer

Should I fill the unvented soffits with foam?

We have an outbuilding that's about 12 x 13 that we want to turn into year round writing / guest room.
It has a basement where well equipment is located. We've sealed and insulated the ceiling and the floor joist bays above the foundation and covered with 5/8ths wallboard. With a tiny heater that comes on intermittently in the cold weather, the basement stays about 42deg F so the pump doesn't freeze.
We plan to improve the ventilation for the warm months when some condensation occurs.

Asked By Rob Cramer | Dec 4 14
11 Answers

Flat roof with no gases or fumes


I am renovating a home in Laguna Beach CA and redoing the roof as well as most of the house. I am highly sensitive to chemicals and the engineer is calling for the following:

1. Ply
2. 4” High Density Rigid Insulation Foam
3. CDX sheeting
4. Mule Hide roof system

I am wondering if you have any suggestions about how to create a gas/vapor barrier so that when the roof heats, I am not exposed to fumes/gasses from the materials. The inside will be finished with 1/2” drywall board.


Asked By Kimberly Norton | Dec 2 14
17 Answers

Insulating an unheated basement / cellar

Hello everyone,

Thank you for the great site and apologize in advance for lengthy first post.

I have a small room (6'x20') in the basement that is currently unheated and uninsulated under covered porch. Ceiling and walls are concrete and there is no visible water penetration. There is exterior door separating this room from the rest of the finished basement (conditioned/insulated)

Asked By Chris kim | Dec 2 14
35 Answers

Best heating/cooling method for a new 5,000-square-foot home?

We are building a very different home in Prince Edward Island (Northeastern Canada). It's a Deltec home ( from North Carolina & very energy efficient from a design aspect (i.e. less drafting due to its round nature, etc.). We are doing a 2 level, with each level being 2,500 sq. ft. The basement is about 3,000 sq. ft., is perfectly round, & made using ICFs.

The 1st level will be divided into 4 x 625 sq. ft. rental units and the upper level (2,500 sq. ft.) will be where we live.

We will be adding solar panels to the roof at a later date.

Asked By Steve Arnold | Jan 2 13
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