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7 Answers

Spay foam on the inside of poured foundation to avoid mold?

I have a question regarding insulating a new construction poured foundation in zone 6B, close to 7A. Twenty miles north of Minneapolis.

Originally I was planning on either a T-Mass or ICF foundation. Both are somewhat more expensive and have a lower R value than what I am now proposing. The current plan is to insulate the outside with 2" foam sheets. This will satisfy code. Then on the inside I would spray 2" of foam and insulate a stud wall with either Rockwool or fiberglass. This wall would be around R-30.

Asked By jim sweazey | Mar 26 17
6 Answers

Adding exterior insulation over stucco

I have a client who is looking at remodel and wants to improve the insulation and sealing. This is a rental property and wishes to minimize cost. The exterior is stucco (45 Years old) and I want to know if there is any way to insulate on top of the stucco and then provide a new exterior. Will be taking the interior down to studs.

Location is Western Canada, Souther Alberta.

Thanks for the thoughts

Asked By Christopher Houston | Mar 27 17
3 Answers

Perlite insulation?

Mineral wool is a popular insulation recommendation, but it seems expensive and has limited supplier options. I came across some info on perlite (and even vermiculite and lightweight expanded clay aggregate [LECA]) as a potential insulation material. I realize that it has a lower R-value per inch than others (perlite loose fill at 2.7/in, vermiculite 2.08/in), but if wall thickness were not a limiting factor, would it be a worthwhile consideration?

Asked By Stuart Miller | Mar 27 17
8 Answers

Building a new house, looking for opinion on insulation/exterior foam combinations

I am currently in the process of designing a new home. I built one four years ago that we have decided is too big and inefficient for what we need. This time around I am looking to build small, simple and efficient. The house will most likely be framed with 2x6 walls, however I would like to maximize R value of that wall.

Asked By user-6801629 | Mar 23 17
3 Answers

Different one-part foams

Hey folks,

I'm installing XPS/EPS rigid foam against my basement walls. I've seen and read on FHB using low-expanding as the adhesive to hold the foam on the walls. I'll be framing a 2x4 wall in front of the rigid foam, so the adhesive only needs a moderate hold.

Great Stuff Window & Door is by far the most common spray foam I see. Its in the big box stores, Amazon, etc. I've put up a few rigid foam sheets in the basement as a test with the Great Stuff and the hold is fine.

Asked By Jamie Royal | Mar 26 17
6 Answers

Building a new home in Climate Zone 5 — Need insulation help

We are building a new home in zone 5 (Michigan) and I would like your recommendations on how you would insulate the walls and roof/attic space.

The home is 3500 sqft with 2750 on the main floor and 750 upstairs. The main living space (kitchen, dinning, living room) is open concept with a cathedral ceiling. Other areas have a more traditional attic space.

The basement will be unfinished and we will use 2" rigid foam under the slab and on the walls. (unless you tell me differently)

Walls are 2x6 construction.

Asked By NKoenig | Mar 26 17
0 Answers

Dense Packing Cavities within Cathedral Vault

I'm preparing to have my attic spray foamed and decided to dense pack the cathedral vault cavities with cellulose. The existing cavities contain batts. Two questions:

1. Is it ok to blow in cellulose on top of the batts or should I fish them out?

2. Should I seal off all the soffit vents (with spray foam) under the eves of the cathedral vault since I'm dense packing the cavities to further prevent any airflow into the cathedral cavities?

3. Should I also spray foam all the soffit vents around the entire house to further promote sealing off any airflow from entering?


Asked By uberaustin | Mar 27 17
8 Answers

Low-slope "warm" roof build-up clarification

We are advancing on the planning stages of a new build project in climate 4C (near Vancouver, Canada). Thanks to the many articles and Q&As on this site I've got myself comfortable with most outstanding issues we are facing in developing our roof and wall build ups. This is a small building used as a holiday home, not fully occupied in Winter.
With that in mind any feedback from your good selves would be appreciated.
The roof is a mono pitch (shed style) front to back at just 1:12 with no "rafter" space to hold insulation
Build up:
- Exposed 3X8 Douglas fir beams

Asked By Quinn Sievewright | Mar 26 17
0 Answers

Duct Insulation Sleeves - Black PP or Reflective Foil?

Right out of the gate, I am NOT talking about foil faced bubble wrap duct insulation. This question is specifically in regards to FIBERGALSS INSULATED DUCT SLEEVES. :-)

I see generally two types of fiberglass insulated duct sleeves available; those with some sort of plastic covering and those with a reflective foil type covering.

I would assume the foil covered types might be intended for use in an unconditioned attic with high summer temperatures? But my question applies to using these products within the conditioned space.

An example of both products can be seen here:

Asked By Lance Peters | Mar 27 17
1 Answer

Climate Zone suggestion

Given the importance of climate zone to the nature of this forum I would highly recommend that it be a required drop down field in the "Create Community Question" pages.

Asked By Edgar Pankey | Mar 27 17
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