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4 Answers

1 1/2 story farmhouse in British Columbia

Hi, I'm looking for some thoughts on our current design for our 2000 sqft home.

In Plans Review | Asked By Michael Blake | May 22 18
11 Answers

Spray foam from crawlspace onto bottom of plank subfloor in Pacific NW?

Hi there - I'm in a 1955 house in Seattle, WA, over a vented, unconditioned crawlspace, with hardwood flooring on top of plank subfloor with no insulation under it.

In Energy efficiency and durability | Asked By Frasca | May 21 18
3 Answers

Air sealing near soffit question

Hi there everyone, first time poster here. I am in the process of air sealing my attic, in addition to installing baffles so that I can add insulation on top of the existing fiberglass batts that are in between the joists in my attic.

In General questions | Asked By DrJimesTooperMD | May 23 18
4 Answers

Is it worth creating a conditioned attic for my house?

I live in North Alabama, zone 3a I believe. I have a 25 year old, 1375 sq. ft. house on a slab with duct work in the attic. I have already paid a home performance contractor to seal the ceilings and top walls, add blown in insulation, and replace and seal ductwork. They also performed the door air blower test for air exchange rate. I have a bedroom that is always hotter or colder than the rest of the house.

In Energy efficiency and durability | Asked By CGFears | May 23 18
3 Answers

Spray Foam Unvented Ceiling

Hello, new to this forum and I've seen a lot of good information in what I've read so far. Hoping to get some advice on how to insulate a ceiling in a detached office/accessory building on the Oregon Coast. I rebuilt an old garage and created a single pitch 2:12 unvented ceiling. Rafters are 2x10, uninsulated metal roof on top. I was planning to spray foam 2" of closed cell in the ceiling cavity. My question is do I need to fill the remaining cavity with batt or something else or could I leave 7 1/2 inch gap between the foam and sheet rock?

In Energy efficiency and durability | Asked By Dan McGuire | May 22 18
10 Answers

Double stud wall sheathing / air sealing

Hi All,

Thanks in advance for any suggestions/comments/advice.

I am in the framing stage of residential home in central NC (Zone 4A). The exterior walls have been designed as a double-stud 2x4 assembly.

The interior double stud has been spec'd to be sheathed with 1/2 in CDX w/ taped joints and r-15 Roxul batts, cavity insulation as dense-pack cellulose to r-20, and exterior double stud finished off with another 1/2in CDX, followed by WRB, 1/2" vertical furring for rainscreen, 3/8" horizontal furring (to accomodate for Hardie board and batt siding.

In Energy efficiency and durability | Asked By Corcakalaka | May 22 18
10 Answers

Exterior sheathing and insulation

Hello new member here. Plan on building a home in TN, climate zone 4A. Want to make this home very efficient and comfortable. Planning on geothermal ground exchange HVAC as no natural gas is available in the area. My question is around exterior wall insulation.

In Energy efficiency and durability | Asked By Cdgatti | May 21 18
2 Answers

Merits of removing masonry chimney?

Hi all,

The sixty year old chimney at my 50s ranch is severely damaged from moisture kicked off by our hot-water heater (now replaced with an indirect WH off our boiler). I've received several bids to have it rebuilt but I have a different idea. I am thinking of tearing down the chimney to below the roofline, insert a round metal chimney vent in its place, and finally roof & CC sprayfoam the cavity left behind. Rather than a 6' by 3' chimney I'd then only have two 6" metal pipes (basement & 1st floor fireplaces). The chimney is in the back of the house and adds nothing aesthetic.

In Energy efficiency and durability | Asked By Brian Gray | May 22 18
1 Answer

Attic open-cell foam: off-gasing / odor

We have a traditional 1966 two story home, dual-zoned home in Atlanta (zone 3A). On April 18th we had our existing inadequate fiberglass insulation removed and open cell foam installed in our 1200 sq ft attic. We have had odor / off-gasing problems since. On cool, cloudy days it’s not very noticeable but on hot, sunny days the odor is quite pronounced and our second floor A/C (handler in the attic) is not usable as it blows in the odor/gases. We’ve been living with open windows and fans upstairs since. The odor is closer to the paint-like I have read about, not the fish-like.

In Green products and materials | Asked By User-7075353 | May 22 18
12 Answers

Exterior Insulation on Cinder Block Walls

I have been through many articles talking about exterior insulation techniques, and insulating the exterior of foundations. My house is a little unique, and I'm hoping that someone can offer some insights/guidelines on how to handle things.

In Green building techniques | Asked By Jameson Taylor | May 18 18
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