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3 Answers

Sight-built SIPs detail -- leave the middle foil face?

As a follow up question to a previous one:

I am going with the "sight-built sip" approach.

Zip sheathing taped then a double layer of 1" eps foam and 1/2" osb on the outside with an additional layer of building wrap.

The sheets came foil faced.

Q:Does it matter if I leave the foil on the 1" layer attached to the sheathing? (sandwiched between the 2 layers of foam) Will it interfere with moisture flow away from the house?

It peals off fairly easily so that is an option.


Asked By Brian McDonald | Oct 5 15
1 Answer

Mfg. home, block skirt insulation

I am setting a 25x65 mfg home on a full slab foundation in zone 5+, high desert Cascades. I will be putting in a 3 course cement block "skirt" with mechanical ventilation. I am considering installing 2" rigid foam panels 24"x48" attached to the inside of the block skirt. I am looking for heat retention in the winter primarily (-20 on occasion). Will this be worth the effort and expense??

Asked By Robert Holland | Sep 27 15
5 Answers

Can I place foam insulation over linoleum tile in a basement floor?

I'm attempting to remodel a basement that is conditioned space in climate zone 4A (MD).

Asked By John Sullivan | Sep 25 15
12 Answers

How to insulate rim joists & above grade basement walls in older home without using foam?

I'd appreciate input on how best to insulate/air seal an older basement without using foam (rigid or spray). I've gotten input from a few several weatherization folks, but the information varies and seems pretty expensive. I'm looking for an affordable solution that will work. (Photos are attached).

My goal is to 1) air seal and insulate the rim joists, 2) air seal the above-grade brick. I will eventually insulate the brick when budget allows.

Asked By Theresa Spear | Sep 14 15
5 Answers

Crushed rock or plumbing rough-ins first?

New construction, Superior Walls & slab on grade (daylight on 3 sides, against an upslope bank).

After leveling and compaction, the excavator will provide 8" of crushed stone leveled and compacted for both the Superior Walls (first), then the slab that will be poured to them.

Asked By David McNeely | Sep 15 15
13 Answers

Basement walls

I am building a ranch home and most of the basement (2800sqft) will be finished as living space. The builder has the waterproofing membrane spray on the outside of the basement, the plan calls for 2x6 with r21 insulation batts, and a certainteed membrain. There are drain tiles on the interior of the basement walls and the exterior. There will also be 10 mill poly underneath the basement slab when it will be poured.

Asked By D L | Sep 9 15
2 Answers

Flat roof — sloping and insulation

I own a custom 2-3 story hillside 3300 square foot island home in Gig Harbor, WA (Climate Zone 4C) that was built in 1972. I am the second owner and purchased the home in 1986. The house roofing consists of 80% metal on a 6:12 pitch and a 20% flat roof (~560 square feet) over the bedroom wing with eight ceiling can lights adjoining clerestory windows. The house plans specify R-19 fiberglass batt insulation. The flat roof was replaced in 2001 with a ridge vent and torch down installed.

Asked By Mike Hirko | Sep 11 15
6 Answers

Unvented roof, Zone 3B, foam-free

Hi Martin,

First off, I have read a wealth of articles on the subject of unvented roofs, by yourself and Joseph Lstiburek. I started with your “How to Build A Cathedral Ceiling” article and read pretty much everything related to this from you and Lstiburek. The conclusion being that for an unvented roof you either install closed-cell spray foam between the rafters, or rigid foam above the sheathing at a thickness dictated by your climate zone to keep the sheathing warm enough.

Asked By Joe G | Aug 26 15
5 Answers

New 20+ SEER Variable Carrier heat pump w/ Greenspeed Intelligence system creating moisture & performance problems in the crawl

I had to replace 2 -13 SEER HVAC split systems in my house about 2 years ago do to some Sandy storm damage. One split system was a 90% gas furnace with a 3 ton 13 SEER AC and the other was a 2 ton 13 SEER heat pump.

Asked By Bruce Howe | Sep 2 15
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