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2 Answers

Can polystyrene foam be used as a thermal break on inside of exterior osb sheating?

I am in zone 5 and building with 2x6 framing that will be filled with 5.5 inches of open cell spray. I know that 1/2" is too thin for the exterior but have not seen any comments about putting it on the interior side of the osb . Thaks, Ohio Mike%

Asked By user-7030272 | Jun 1 18
11 Answers

Is sheathing a metal roof necessary?

I'm a carpenter here in Asheville,NC zone 4/5 and trying to design a home for myself so I need to make it as inexpensive and green as possible. I'm thinking of a shed roof using flat trusses with blown cellulose to R-60 and a metal roof. Of coarse, there will be eave and "ridge" vents. So do I need to sheath the roof for metal or will just using purl-ins work. My main concern in condensation. If you dont think this would work could you suggest other systems that would be inexpensive labor is less an issue since I will be doing most of the work myself.

Asked By terrell whitworth | Feb 20 13
4 Answers

Inverter vs. regular minisplit vs. window AC unit

I have a summer house in Monterrey Mexico, 150 miles south of US-Mexican border.

Average summer temperatures are 32-38 celsius, with peaks of 42-44, and lows of 25-30 celsius.

The area to be cooled is the top 2nd floor. The house was built in 1960, with mexican cinder blocks (not as dense as american). There is 0 insulation. The ceiling is like tic tac toe squares of concrete beams with Styrofoam filling the gaps, covered with 2 inches of concrete on top. The roof has a type of liquid water-proofing mopped over the top every 3-4 years.

Asked By Atgblue1 | May 29 18
22 Answers

Double stud wall advice for Zone 6

I know Martin wants us to move on from wall design, but I really need help.

I am in St. John's, Newfoundland, zone 6, lots of driving rain, little use for A/C in a home, supposedly like Bangor, Maine.

Double stud seems like the least expensive option for a high R value wall. I've already priced dense pack cellulose installed, and quite frankly I can buy and self-install mineral wool batts at about 70% of the cost, so given the advantages of mineral wool, that is my preferred option.

Asked By Steve M | May 29 18
3 Answers

Vented cathedral ceiling and vapor barrier

I am renovating a small cabin in northwest Oregon (climate zone 4 marine) which has two intersecting cathedral ceilings. One is exposed T&G to which I will eventually add insulation above the roof, but the other is a vented 2x12 rafter with a continuous ridge vent (standing seam metal roof). I was planning on making a 1-1/2" ventilation air gap with a site-built baffle from 1-1/2" foil-faced polyiso foamed in place, furring down the rafters with strips of 1-1/2 polyiso and 1x3 strapping to make room for R38 batt (as well as insulate the rafters).

Asked By Peter Stevens | May 30 18
8 Answers

Fujitsu and LG Ductless Mini Split Reliability

I am in the process of adding A/C to my house and I need help with choosing the right equipment. I am update an old 2 story colonial in the Boston area and I am looking to add the ductless heatpump to supplement the oil heating (No gas available on the street). I have the Manual J done and the heat load will be 47000 BTU and the cooling load will be 28000 BTU.

Asked By Bing Yu | May 29 18
8 Answers

Incorrectly installed spray foam remediation?

During a major remodel with the house vacated open cell Demilec APX was applied under the roof sheathing to create a conditioned attic. A Demilec rep was on site for three days. A strong odor remained for months. A different Demilec rep sent a sample of foam to their lab. Results were it wasn't applied thick enough, so it lacked the exothermic reaction to properly off gas in 72 hours or less.. The installers acknowledged the problem, pulled (48 days after application) the new ceiling drywall and removed +90% of the foam. During removal I kept foam samples and had it tested by Eurofins.

Asked By Brad Dorken | Jan 29 14
1 Answer

Exterior Doors

Do energy star doors have argon between the panes? We are getting a patio door (inswing) from Waudena/Taylor because they offer a 13" frame, but they just use air in between the double panes.


Asked By user-6870177 | May 29 18
12 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
1 Answer

Insulating garage ceiling below bedrooms

Hi everyone, I have a split ranch with a 2-car garage under the bedrooms. The back wall of the garage is completely below grade, the left wall is half below grade (slope), the right wall connects to the 1st floor and the front wall has two 8x7 insulated doors. There are no windows, the joists are 9" tall, and I am in Massachusetts.

The ceiling is currently drywalled and i could see some R-9 batts through a gap.

The bedroom floors, particularly at the front of the house, get quite cold in the winter.

Asked By Mike93lx | May 27 18
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