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1 Answer

Unvented attic and wall?

Zone 3, 12/12 pitch roof, Galvalume color roof.
Talked to insulation contractor and discussed options.

2x6 walls = Hardie lap siding, 3/8" rainscreen, Tyvek, OSB, air sealing, BIB insulation (R-23), 5/8" sheetrock.

2x8 cathedrial roof, unvented, with total elect units and ducting in kneewall area and spare room in the center = standing seam, membrane?, 7/16" OSB, 2 inch polyiso, membrane or taped joints?, 7/16" OSB, 7 inch open-cell or BIB insulation.
No venting.

Are we getting closer?

Asked By Quinton | Nov 29 15
1 Answer

What is the most economical heat system for a 700 s.f. house with no furnace?

I have a relative who may have to give up her house due to illness/unemployment Her gas furnace went on the blink. To replace it would be $1800 +. What is the safest most economical method of heat to heat her 775 sf house. She closes off one room so actually 3 small rooms & a bath is what she would be heating. For now she is using an electric fireplace and two infrared heaters that are supposed to heat up to 1000 sf.
Thank you.

Asked By Ruby | Nov 30 15
1 Answer

Green / Passive House Architects

Anyone know of a good source for good energy efficient / Passivehouse architects?

Asked By Peter L | Nov 29 15
7 Answers

Insulating a non vented vaulted ceiling in Canada


I've recently had a 10x14 foot backyard studio built for me by a local company. I asked them not to insulate it because I was hoping to save some money by doing it myself. However, after some research I'm not really sure how to continue.

The studio has a vaulted 2x6 ceiling (with one skylight) with no ventilation. The soffits also have no vents. Initially, I was planning to just shove some fibreglass batts up there, putt up a vapor barrier and then finish it off with some wood paneling. However, after researching it sounds like that's a recipe for moisture and mold.

Asked By Kirsten Quist | Nov 28 15
1 Answer

Masonry block wall: To seal or not to seal?

In preparation to insulating my renovation of a 1970s building's masonry block wall with 2" XPS foam board attached directly to the masonry block, should I paint the interior masonry block wall with a sealer like DRYLOK® Masonry Waterproofer or KILZ 2® LATEX Low VOC?

Right now there is a thin coat of cheap latex paint on the block wall.

Russ :-)

Asked By Russell | Nov 29 15
3 Answers

Best practices for HRV on a budget

I am building a simple but efficient home in climate zone C4. It will be a 3 bedroom, 2000 sq ft home. with us living mostly in the upper half. I was originally planning on putting one or two panasonic spot ERVs in but am know thinking it might be better for overall air quality, efficiency, and spreading the heat from my two headed mini-split, to put a fully ducted HRV unit in. I have been looking at the Fantec FLEX100H, and the Lifebreath RNC 95. Money is a huge issue but the price difference between two panasonics and one of these units is not much.

Asked By Kail Zuschlag | Nov 29 15
3 Answers

Adding foam board to ceiling rafters?


The rafters in my ceiling are only 2 x 6. Is it acceptable to lay polyiso sheets across the top of the rafters, or should I be concerned about the foam acting as a second vapor barrier? The fiberglass batts have a kraft liner facing the sheet rock.

If the answer to the above is yes, can I place the foam in between the rafters against the sheet rock under the fiberglass batts?


Asked By Donald Mendell | Nov 29 15
1 Answer

Questions about insulating 1947 concrete block home in Florida

We purchased a house in Orlando that we plan using as a rental. It is a one story block home, about 850 square feet. As with most houses built here during that time period it had no insulation with the exception of some blown in cellulose in the attic. We have gutted the house and found that originally there was no furring strips and drywall on the inside of the exterior walls, they have been painted and wall papered a couple of times then someone furred them out and put up wood paneling.

Asked By Nathan Vaughn | Nov 29 15
4 Answers

Pros and cons of Grace Ice and Water compared to Tyvek Drainwrap

If applying a WRB under rigid foam insulation, what are the pros and cons of using Grace Ice and Water Shield compared to Tyvek Drainwrap, in terms of protecting the sheathing, serving as an air barrier, difficulty of installation, flashing details, and any other reason you might prefer one product over the other to serve as a WRB? Assuming that the Grace product is more expensive, do you believe that it is worth the additional cost on a 2,000 square foot home in Zone 5?

As always, any advice or opinions are greatly appreciated.

Asked By James Timmerberg | Nov 29 15
2 Answers

Recommendations for a small HRV

Hi everyone
I'm looking to buy an HRV for our small (1000 sqft) ranch home.

I already installed all the dedicated ductwork last year and had been using a home-made HRV that worked very well, but I don't have the time to keep tinkering with it to get it to work just right. The cabinet was made of plywood and I kept having problems with the air streams crossing and causing condensation and mold in the cabinet.
Anyway as a result I'm going to hook up a new HRV to my ductwork.

I'd like a small unit - I will be installing it in a closet
Quiet would be good
Also with ports on top

Asked By Carlo Giombi | Oct 12 15
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