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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.

Asked By CGFears | May 23 18
2 Answers

Difficulty finding a modulating multi-zone air-source heat pump

I need to finalize the equipment selection for my current build. My engineer along with Mitsubishi spec'd a City Multi (VRF) PUMY outdoor unit with multiple indoor units. Unfortunately, this outdoor unit does not have hyper-heat, which means that in order to meet the 99% heating requirements, it will be grossly oversized for cooling. While the compressor can operate down to low-20% of rated capacity, that is still much higher than an MXZ minimum operation for the same sized unit.

Asked By Jonathan Lawrence CZ 4A New Jersey | May 21 18
1 Answer

Vaulted / Cathedral Ceiling -- Unvented

Hi, I'm in the process of building a cabin near Saskatoon, Saskatchewan, Canada. I can't tell for sure since the climate zone map is for the US only, but I'm guessing this would be equivalent to Zone 6B or 7B.

Asked By User-7075735 | May 23 18
0 Answers

Fasteners for concrete, brick, and CMUs

For an upcoming article on fastening various materials to concrete walls, brick walls, and CMU walls, I'd like to hear about your favorite fasteners.

I'm looking at fastening three types of materials:
1. 1x4 furring strips directly to a concrete wall, brick wall, or CMU wall.
2. 2x4 furring strips directly to a concrete wall, brick wall, or CMU wall.
3. Continuous rigid foam (2 inches thick or more) directly to a concrete wall, brick wall, or CMU wall.

I will also look at a fourth situation:

Asked By Martin Holladay | 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?

Asked By Dan McGuire | May 22 18
1 Answer

1 1/2 story farmhouse in British Columbia

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

Asked By Michael Blake | May 22 18
8 Answers

Spray foam questions

Hello all, thanks for any help in advanced.

Asked By Stanger133 | May 20 18
10 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.

Asked By Frasca | May 21 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.

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.

Asked By Cdgatti | May 21 18
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