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7 Answers

Does Reflectix "Big Bubble" insulation really achieve R-6?

I have seen several discussions here about bubble wrap insulation for ducts (some links below). However, they are all a couple years old, and they don't seem to directly address one of Reflectix's products. The older and smaller products were generally met with great skepticism because they claimed high R values without clarifying that the installation required an air gap between the duct and the bubble wrap.

In Energy efficiency and durability | Asked By huhnra | Apr 16 18
5 Answers

Roof ventilation

I have a low pitch (1/12) single slope shed roof on my house. (Marine Zone 4c near the coast with very little snow and ice) The framing is 2x8 filled with insulation. Drywall on bottom and skip sheathing on top- no ventilation. The existing roofing is built-up asphalt.
I plan to remove the built-up roofing and install 2" of polyiso, then 1 and 1/2 inches of EPS, 5/8" of plywood, then a standing seam metal roof with mechanically seamed joints.

In Energy efficiency and durability | Asked By EASimonsen | Apr 14 18
5 Answers

Product compatibility of wall assembly components for Climate Zone 4a

I am in the planning phases of a new home for my family outside of St. Louis, MO. I'm having a hard time pulling together all the compatibility issues that worry me when detailing my wall assembly. I am striving for a tight house that is well insulated, but not necessarily trying to achieve any recognized benchmark. I would hope that with a future PV array I could be close to net-zero with my goethermal HVAC system planned for. Here is what I am have at least planned for at this point: (from inside to out)

- 5/8" Drywall

In General questions | Asked By Nate Droste | Apr 16 18
13 Answers

EPS, XPS or Polyiso for exterior rigid foam?

Last week I got some great information from this board on my "Taping seams of roof sheathing" question. There was some thread drift there and we started talking about exterior foam and someone suggested I use Polyiso instead of XPS for my exterior foam.

In Green building techniques | Asked By Steve Mackay | Mar 28 18
1 Answer

Best/cheapest way to waterproof a concrete deck?

I have a 20X20 concrete deck above my basement, at the end of my driveway. It is made up of 4'X20 concrete slabs. When it rains, the joints leak. I am trying to turn my basement into a workshop, but haven't because of the water issue. I live in the mountains at 5000 ft. if that makes any difference. I am looking for a way to apply the waterproofing material myself, but everyone wants to do the job for me. Which makes this project prohibitively expensive. I would appreciate any suggestions.

In General questions | Asked By eggdood | Apr 16 18
2 Answers

Insulating a Non-typical Cathedral Ceiling

Insulating a normal cathedral ceiling has been covered by GBA in Martin Holladay's How To Build an Insulated Cathedral Ceiling .

In Energy efficiency and durability | Asked By Steve Robertson | Apr 13 18
1 Answer

Radiant heat system to go under ceramic tile on a concrete floor ?

Trying to find a radiant heat system to go under ceramic tiles in bed room. Don't know enough about them to pick the best one and still not pay a small fortune..

In Energy efficiency and durability | Asked By nuclear free | Apr 14 18
5 Answers

Best tape for OSB?

Ok, I have given up on finding much local.

I can get Sega Wigluv 100 2 1/4 for about $60 a roll


I can get Zip tape for $26 a roll 3.75 x 90

In the Texas A&M outdoor exposure tests the Zip tape was looking quite good, and I think it performed well in martin's backyard test of tapes also.

I know wigluv is really really good stuff, is it worth ordering online and paying a bit over twice as much ? Or is Zip tape going to get me a similar result.

Note, this is not on zip, but on OSB, in Austin Texas.

In Energy efficiency and durability | Asked By Sleaton | Sep 6 17
2 Answers

Can I use Grace Ice and Water Shield on my basement floor for as a moisture barrier?

I live in northern VT and we're re-finishing our basement. Our basement is cool and damp but no water or excess moisture. We will be spray foaming the walls and I also want to put down a moisture barrier on the floor which will be carpeted. I can't put down anything too thick due to the stairs but I want something durable and also not slippery due to the carpet. I'm wondering if I can you GRACE Ice and Water Shield (or similar roofing underlayment) as a moisture barrier. I also like the fact that it has an adhesive so it will stay in place.


In Energy efficiency and durability | Asked By Willy1 | Apr 16 18
17 Answers

Closed Crawl Spaces/For Ted Clifton

I have read with interest Ted Clifton's comments on closed crawl spaces, in which he advocates insulating the walls AND the floor (eg, comment #9 here: here). But, I'm unclear on teh recommended R value for floors.

What R value insulation should we install in the crawl space ceiling?

In General questions | Asked By Emerson | Apr 1 18
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