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9 Answers

In addition to my other post I would like to know about the best approach for certain areas of the house here are my concerns

ATTIC: 2" of open cell foam along bottom cord of trusses to seal drywall, also spray foam where top plate and drywall come together, also where insulation baffle meets top plate. 12 inches of blown cellulose on top of the foam
QUESTION: Is this a good plan to seperate the attic from the conditioned part of the house?

BONUS ROOM OVER GARAGE: 3" od open cell in ceiling of garage to keep floor warm

In Energy efficiency and durability | Asked By Anthony Hughes | Aug 8 14
9 Answers

I have a Cape Cod style house that we had the roof sprayed with Open Cell foam. We plan to finish off the upstairs for living space. My question is that If we plan to use liquid vapor Barrier primer/paint do I need to paint all the foam, or can I get by with just spraying the drywall only. Do I need to spray behind the knee walls or will the drywall on the knee walls be sufficient? We do live in central Wisconsin.

In Energy efficiency and durability | Asked By Dave Meyer | Aug 3 14
4 Answers

How are those of you using this product detailing the bottom of the wall where the Roxul is exposed?

I noticed on one post about a project in BC, they used a perforated galvanized channel to encase the bottom of the IS. Does anyone know where to source a channel like that?

I'll be using 3" Comfort board over 1/2 CDX sheathing, over 3/4" x 3" furring strips, then cedar shingles.


In Green building techniques | Asked By Edward Krause | Aug 8 14
34 Answers

I'm looking for an air-to-water heat pump and feedback from those who've used them. We have a LEED for Homes project in Victoria, BC, perfect climate for heat pump, affordability of project prohibits groundsource for 36Kbtu heat loss of 1800 ft2 home and for optimal comfort, low temp/efficiency, to avoid ducting we're selected hydronic in-slab for heating distribution thus standard air-to-air heat pump is a no-go.

In Mechanicals | Asked By Allison Ashcroft | Jul 28 09
2 Answers

ok. I live in the South (Lower Alabama) and my bonus room above my garage, gets warm during the summer. I went in the attic today to see how the insulation was installed and I noticed that it is Paper towards the room (insulation towards the hot attic space). I read a few articles where basically is states that it doesn't matter (or depends) on which way the paper faces.

In Energy efficiency and durability | Asked By Nathan Jones | Aug 8 14
8 Answers

I'm going to be building a 28x40 (aprox 1500sf living) chalet style house in upstate NY CZ6 (design temp 6f) it will sit on a walk out basement (one narrow end walk out the rest under ground) I am going to put pex in the slab even though I don't currently plan to ever need it warmer than 55 or so down there.

Been reading on the subject quite a lot, and think that the pretty good house concept you guys have come up with is a great idea, and should get me in a balance point between up front cost, and monthly utility bills.

In Energy efficiency and durability | Asked By Trevor Chadwick | Aug 4 14
12 Answers

Hi, I’m going to have a new house built and am confused on where to spend additional money in regards to insulation and air flow.

I have talked with many builders and most offer a “standard” solution involving fiberglass batts in walls for insulation and no air control layer (other than drywall or caulking holes that they find from blower door testing).
If I am interested in anything better it will cost me more money.

I understand that “batt” insulation can be problematic in regards to having it installed correctly.

In General questions | Asked By Ani Brown | Aug 6 14
2 Answers

The main question is whether the air space provided by the metal ribs would provide adequate air flow. If not, how about vertical 2X 'purlins', forming site-built insulation baffles that would be insect screened at both ends?

In Green building techniques | Asked By Michael Roland | Aug 7 14
4 Answers

Following up on last month's blog about building codes, am I correct that the code allows interior vapor retarding with latex paint on sheet rock? Also, does the vapor permeability of ZIP sheathing prevent inner wall condensation without the use of exterior foam?

In Building Code Questions | Asked By Michael Roland | Aug 7 14
5 Answers

I am using vented soffitt with baffles and blown-in fiberglass or cellulose. Ridge will be vented with 'Core-vent' type vent.

Forgot to say, using metal roofing.

In General questions | Asked By David Parker | Aug 7 14
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