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6 Answers

Insulating first floor of a plaster house

We live in a 5A-6 zone on the Hudson Valley in NY - the house was built in the early 40's...the house is essential one story which has plaster walls. We are converting the upstairs to a bedroom and bathroom with drywall.

I have read mixed reviews about adding insulation to the existing plaster walls. We would like to use fiberglass in the attic - drywall area and we were going to remove the siding and a couple sheathing boards to fish thru fiberglass on the first floor plaster walls. Is this a bad idea? Is there a better way of insulting plaster/drywall combination walls?

In Energy efficiency and durability | Asked By Jhorton1214 | Apr 12 17
4 Answers

Effect of spray foam on AC refrigerant lines & electrical wiring

Finally we are ready to make our attic a conditioned space. R38 on 2x6s and R21 gable walls. The new closed-cell Demilec HFO looks very promising. After all the research, I’m done to one major concern:

In Mechanicals | Asked By David Goldman | Apr 11 17
6 Answers

Mitsubishi or Daikin minisplit ductless?

I am building a new construction house and will be installing a ductless minisplit system for heating and cooling. I have chosen this route because I want ductless and for energy efficiency.

My question is: Should I go with Mitsubishi or the Daikin system? Daikin costs less and has a better warranty. But what about performance and energy efficiency? Can anyone answer this question? Thanks.

In Energy efficiency and durability | Asked By user-6813968 | Apr 11 17
26 Answers

Mold/ventilation problems in an old passive solar house

I just tried to post a long comment on the vapor retarder/barrier article and was blocked for spam so I'm trying again here. I'm under contract for purchasing a 1979 passive solar house in Southern Maine (near Sebago Lake, but at higher elevation). The house needs a lot of work, which we were expecting, but on top of all that they unfortunately found moderate to high mold growth on the roof sheathing and rafters, along with improper insulation/ventilation practices.

In GBA Pro help | Asked By Movintomaine | Apr 9 17
3 Answers

Insulating a cathedral ceiling

I am building a new construction house and have 9' ceilings except for cathedral ceiling in the living room/family room. What is the best way to insulate the area above the ceiling above the cathedral ceiling? Thanks.

In Energy efficiency and durability | Asked By user-6813968 | Apr 11 17
7 Answers

Too late for outie windows?

I framed and wrapped my house planning on innie windows. Walls will be standard construction with 6” exterior foam. Actually…I installed all the windows that way as well. With that behind me, I am feeling like the structural and performance benefits I based this choice on are overblown, and I’d like to change to outie windows. My rough openings are sized for the windows – not the windows plus extensions. I am trying to determine a way to build rough opening extensions that attach outside the sheathing.

In GBA Pro help | Asked By Jim Tyler | Apr 10 17
0 Answers

Fujitsu minisplit installer in Orangeville, Ontario?

I am looking for an HVAC company to supply and install a Fujitsu AOU48RLXFZ1,etc in our new high efficiency home in the Orangeville, Ontario area.

So far no joy in finding a Fujitsu authorized company to do the work all those I've contacted will not travel beyond their local areas (ie - Toronto, Barrie, etc)

Can anyone recommend an installer for me?



In Mechanicals | Asked By Steve Babcock | Apr 11 17
14 Answers

Final design: Roof, walls, and floor

So getting final details of a new build in Zone 6 (Osaca, ON) Hopefully pretty good house , that will be Net-Zero.
Any comments or suggestions before I finalize this? Thanks !!!

Roof setup:
Standing seam metal roof
Blueskin self-adhered membrane
5/8 plywood
2” air gap
attic truss with raised heal
24” minimum blown in cellulose
1/2” drywall
latex paint

Wall setup Outside to Inside:
Vinyl Board and Batten Siding
1x4 furring strips mounted horizontal 12” OC
2 layers of 2” Silverboard EPS taped seams
Blueskin VP100 ,maybe something else?

In Green building techniques | Asked By Dave B | Apr 4 17
12 Answers

Please help me understand NFRC window ratings

Please help me understand NFRC window ratings.

Are these numbers a fair comparison of window performance? Are all manufacturers rated under the same criteria? I read that some report center of window u value. Are Canadian windows rated under a different value? I understand the European windows use a different system.

I am considering WASCO windows. I haven't seen any other manufacturer with NFRC ratings as good. I have no reason to mistrust WASCO. They have been very responsive and forthcoming.

In General questions | Asked By Jim Sweazey | Apr 9 17
15 Answers

Are there any "green," non-VOC spray foams?

I'm looking into doing closed cell spray foam for my floor, but the hazards really concern me.

I would like my insulation to be green as possible, without sacrificing quality.

I have read that even soy based (or alternative spray foams) are still quite harmful to breath. Is this true or are there any options that have been proven as a green alternative?

In Green products and materials | Asked By greywolf92 | Apr 5 17
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