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1 Answer

Flooring approach in climate zone 3A basement

Hey folks,

I'm planning on finishing by basement and am looking for some advice on the flooring assembly. I posted something similar about the walls a few weeks back. http://www.greenbuildingadvisor.com/community/forum/energy-efficiency-an...

Some quick information: Climate zone 3a, poured concrete slab, no insulation under slab, no bulk water issues so far, new house constructed in 2016.

In General questions | Asked By Jamie Royal | Mar 27 17
1 Answer

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?


In Green building techniques | Asked By uberaustin | Mar 27 17
2 Answers

Timber vs concrete uppermost ceiling

Price not being a factor, does either of these options have any significant advantages or disadvantages over another?

I'm building a 2 story brick and concrete house, but am considering of going with timber ceiling under the roof (which could also end up being flat roof).

The local price will be the deciding factor, but only if there are no serious drawbacks to the timber construction.

So, what gives, if anything?

Sound insulation should not be an issue since it's uppermost?
There is not much difference in thermal insulation?

In General questions | Asked By davor radman | Mar 23 17
7 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.

In GBA Pro help | Asked By NKoenig | Mar 26 17
25 Answers

Hydronic Heating System Hydraulic Buffer Tank vs Hydraulic Seperator

This question might be more appropriate in a plumbing forum but I have had such great and thoughtful responses in the GBA forums I look to here first. This is also a hydronic heating mainstream topic which should be appropriate for GBA.

In Mechanicals | Asked By Roger Smith | Feb 26 17
5 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.

In Green products and materials | Asked By Jamie Royal | Mar 26 17
0 Answers

Taping Seams in Plywood for Health Reasons?

Climate 4C. I am debating the cost and effort of taping our plywood sheathing. Due to a few circumstances, we changed our building wrap to doubled up 60 minute paper, attached to furring strips (closed rainscreen). Alternatively we are considering a hybrid product called Hydro-Tex, which is tar paper that has a drainage plane on the backside. Either way, is there a risk of this petroleum based product causing health problems, which the inhaling of off-gassing? I know most people who tape plywood seams do so for energy reasons, but is it reasonable to do so more for health reasons?

In Green building techniques | Asked By Mike Dominic | Mar 27 17
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.

In General questions | 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

In Energy efficiency and durability | 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?

In Green products and materials | Asked By Stuart Miller | Mar 27 17
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