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2 Answers

Best foam/product to air seal large and irregular penetration

I'm trying to air seal around the intersection of my cathedral roof trusses and the sheathing that rises up to meet the roof deck. I'm left with some one inch to two inch openings where there are diagonals in the truss. It's possible to tape them up but I had hoped to find a foam solution. Is there a foam product that can be a long term solution?

In Energy efficiency and durability | Asked By Geoff Frood | Aug 4 15
4 Answers

Vapor barrier placement — basement sub-slab insulation

475 High Performance Building Supply has just released a new book - High Performance 2X Framing. It recommends that the vapor barrier for basement sub slab insulation (EPS or mineral wool) be placed under the insulation and in contact with the compacted rock fill. This differs from a Roxul mineral wool technical bulletin, the Hammer & Hand Best Practices Manual and other articles I have read that place the vapor barrier on top of the insulation and in contact with the concrete slab. I questioned 475 on this and they responded that they prioritize protecting the insulation.

In Energy efficiency and durability | Asked By Tom Cross | Aug 6 15
1 Answer

Roll roofing and AstroTurf

How do I adhere astro turf to roll roofing to walk on?

In General questions | Asked By William Lynn | Aug 7 15
1 Answer

Looking for a spray-applied window flashing

I work for a custom home builder in the Seattle area, and the majority of our window flashing details have been calling for the Prosco FastFlash system. While this is a great product, it takes a long time to properly install, and I was wondering if anyone had experience with a similar material that can be spray or roller applied.

Checking on Prosco's website, the only spray applied products that I can find are wall coverings that are to be used in conjunction with the FastFlash/Joint + Seam filler.

Thanks in advance for you help.

In General questions | Asked By Saul Kerner | Aug 6 15
3 Answers

Interior vapor barrier with EPS under vinyl exterior

I'm remodeling a kitchen in Omaha, zone 5, and am ready to insulate the stud wall. Here is my concern: the owner recently had vinyl siding applied. As part of the project, the contractor installed 3/8" EPS under the vinyl. The EPS has a plastic film on one side and a foil film on the other. The owner said this was to "eliminate" air infiltration.

So, should I still install a 4 mil vapor barrier on the interior after I insulate the wall? By doing so will the poly create a "wet wall" with the EPS exterior layer?

Dick Ryker

In Energy efficiency and durability | Asked By Richard Ryker | Aug 6 15
2 Answers

Heat pump water heater size and brand

I'm getting ready to pick my heat pump water heater for the house I'm building. I was leaning towards Airtap but they seem to be gone. the house has 3 bedrooms and 2 1/2 baths with one fairly big tub. I am trying to decide on a reliable brand and looking to see what people recommend. I think I need at least a 60 gallon tank but it seems like the resistance electric would kick on a lot less if I got a 80 gallon tank. what are the disadvantages of the larger tank besides a little more surface area for heat loss?

Thanks for any feedback


In Green products and materials | Asked By Andy Kahn | Aug 6 15
1 Answer

AstroTurf on roll roofing?

How do I adhere astro turf, or jute carpet to roll roofing to walk on?

In General questions | Asked By William Lynn | Aug 6 15
6 Answers

Blueskin self adhesive membrane tape is expensive.. I think I have an answer..

I was wandering through the isle at HD and noticed that the (Blueskin) 6" wide tape x 50 ft is $30 but the big roll of membrane 36" x 200 ft is only $128.

It occurred to me that I could either unroll the larger membrane and slice it into 6" (or any width) strips across the 36" width or roll out the length I need (say 72" and cut strips along the length.

Is that a genius idea or as I fear... the two products are not the same. I am hoping the Bakor Blueskin WP 200 is just a giant roll of whats in the 50 ft rolls.

Anyone ever consider this or look into it?

In General questions | Asked By tim brown | Aug 5 15
20 Answers

Cathedral SIPs are sweating in summer

I have a new home built with SIPS, closed cell polyurethane, R40 roof and R24 walls. The SIPs were installed/built spring of 2014, we moved in Feb 2015. The home is timber frame with Metal unvented roof, the roofer did use vertical furring strips and double bubble over felt. We live in KY and are just now getting into high humid summer, and our center ceiling beams are dripping wet throughout the day, causing small puddles on the floor. The ceiling is hot to the touch at the very peak on either side of the center beam. I believe hot outside air is leaking in.

In General questions | Asked By Jeremy Ballard | Jul 12 15
2 Answers

Do you recommend closed or open-cell spray foam on roof sheathing in a finished attic space in Chicago that incl. HVAC system?

Would closed cell spray foam insulation on roof sheathing impair the ability to detect water leaks via the roof? I'm being told by an insulation contractor that using closed cell spray foam in the roof area would cover up any water damage coming from the roof and the possibility of mold issues would be greater than if I used open cell spray foam. Other insulation contractors are telling me to use closed cell spray foam to R-49 on the roof sheathing in the finished 3rd floor space. Which way is recommended?

In General questions | Asked By Christine | Aug 4 15
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