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2 Answers

Comfortbatt/Rockwool/Roxul and temporary compressibility

I have some framers coming tomorrow and have a basement wall being constructed inside the existing wall so as to insulate inside the stem wall. I'm planning on using rockwool comfortbatt at the bottom of the wall to allow for some breathability of the stem wall.

Will I be able to squeeze the 5.5" comfortbatt through a 3-3.5" wide opening (it will expand to full size, once in the wall)?

It hard to tell if it can compress that much, even intermittently, though I'm guessing so.

Asked By rossn1 | May 20 18
6 Answers

Water Testing After Pex Repipe

I live in South Orange County, California, a repiping companies paradise. A massive amount of newer homes are being forced to repipe due to copper failing and slab leaks. The pinhole leaks begin developing between 8 to 15 years after the home is built and sometimes sooner. The theory according to most is that the builders went cheap and installed copper M in the homes, while the water company uses cholormine which the Copper M can’t handle. Most repiping companies will recommend PEX A, but also market USA made Copper L for the repipe.

Asked By JohnZ99 | May 16 18
3 Answers

Low-maintenance siding for Vermont

I am considering changing the majority of the siding (3000-4000 of 5000 sq ft) from weather atlantic cedar rainscreen design to a low maintenance pre-finished siding to save money on a project. Anyone have experience with these and/or recommend other options?

Certainteed Icon prefinished 30 year 16' -
Boral Truexterior prefinished 15 year 16' -
Everlast 12' - prefinished lifetime -

Asked By J M | May 15 18
6 Answers

Improvements in high-R phenolic foam since the disastrous 1980s

So I have been reading about the closed-cell phenolic and noticed the recent blog describing the use R-8/in Kingspan Kooltherm phenolic foam board in a retrofit.

The unique ability of these phenolic foams to achieve high R-values upwards of R-8 per inch seems to be established in testing and experience. However...

Asked By Aaron Birkland | May 6 18
1 Answer

Ultracell Insulation

Has anyone heard anything about the status of Ultracell insulation? I'm particularly curious, since I live close to Buffalo. The website still says its coming this year, and it sounds like they've gotten several million of funding. However, it looks like Bill Hulstrunk, National Fiber's old technical guru, has moved on to another company, and has filed a lawsuit against them.

Asked By John Ranson | May 8 18
11 Answers

Certainteed Membrain: Reviews and opinions, please

New build, climate zone 6a. High altitude snow country. My insulation contractor is really pushing me away from doing a ccSPF on the underside of my sheathing and very strongly suggesting I use this certainteed membrain. Here are my options for roof design for my un-vented 2.5/12 pitch cathedral ceiling shed roof:
A) 14" TJI rafters with 5.5" of ccSPF and 8.5" of netted and blown in insulation
B) 16" TJI rafters with 16" of netted and blown insulation but using Certainteed Membrain - a nylon smart vapor retarder.

Asked By Steve Mackay | May 7 18
4 Answers

I recently had my attic insulated with blown in Greenfiber cellulose.

I had my installer put down a 6mil vapor barrier in between the attic floor joists. I have since learned this was not nessary and may even cause issues with moisture. I live in NJ. It is humid in the summer and the house is air conditioned. The job is not yet finished. Another 5" of insulation needs to be blown in. Should I have the vapor barrier removed?

Asked By dryskin | May 6 18
6 Answers

Acid stain for concrete interior floor

We are looking to stain our new concrete (interior) slab. We have all ready added a pigment to it, so we don't want to cover it with something opaque. I love the look of the acid stains. I have a dozen or so 12X12" blocks from the same pour of concrete to experiment with colors.

We had a friend apply a few colors of Soy based stain and it came out very opaque, basically covering the pigment we added to the concrete. On their web page they say the soy stain in semi-transparent, while the acid stains say they are translucent.

Asked By diane minutilli | Feb 15 12
1 Answer

Foundation waterproofing membranes

I want to specify a spray applied foundation wall waterproofing membrane that is not asphalt based. From what I understand, there's polyurethane and rubber based. What's the difference? Pros/cons of each?

Asked By Bryanw511 | May 4 18
19 Answers

Heated bath floor - system and flooring?

Is there any metric by which to measure the efficiency of electrically heated bath floors? Is there any system that if preferable to others? What about the Schluter Ditra system? If you have one, would you do it again? If so, what would you change about how it is installed?

Asked By c l | Apr 23 18
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