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1 Answer

Unorthodox foamless insulation system

I've been a long time reader and spent countless hours on BSC trying to learn all I can on building science. The biggest thing I've learned is how much I didn't know. Long story short...we have been making improvements to our home, some cosmetic and some as efficiency when they align. This winter our dated central air heat pump tried to catch on fire(long strory) and after a few months of research we successfully replaced it with three mini splits and they are fantastic! It was unplanned but extremely successful.

Asked By russell boudreau | Jun 19 18
40 Answers

Brick house insulation

All,
First of all, I wanted to wish everyone Happy and Prosperous New Year!
I would like to ask for an advice regarding a wall cavity composition. I am in Westchester County, 30 miles north of New York City, climate zone 4. I am about to acquire a brick house (tiny brick, maybe 2-3 inches thick). Single wythe, I believe. I think that brick is just decorative and is not load bearing at all. Only cinder blocks in the basement support the floor joists. Second floor ceiling joists are supported by wood framing.

Asked By Sebastian Smith | Dec 29 17
14 Answers

Roof / wall connection showing vent above structural sheathing

I know this has been discussed a thousand times here but each situation is unique and I find that answers seem to vary depending upon the mood of the commentator.

I had previously developed a similar detail as the one shown which had furring strips below the sheathing allowing the vent channel to run below the sheathing but I believe this introduces a whole host of problems not the least of which is an area of loose fabric above my dense packed rafters which overtime could become home to a whole host of critters which might then crawl though it.

Asked By Ethan T | Jun 15 18
3 Answers

Shingles over rainscreen over Roxul

Any tips on installing shingles (cedar or fiber-cement) over a rain screen, which is installed over 1.5" of exterior mineral wool? I was thinking vertical furring strips fastened to the studs, then horizontal furring strips on top of those to provide a shingle nail base. Sounds like a lot of extra work but the only other way I've seen (in one of Martin's articles) is to install horizontal strips with dado cuts on the back, which sounds like even more work.

Asked By Phil Boutelle | Jun 1 18
14 Answers

Do I really need any acoustical sealant?

So at this point my sill plate will have Henry CM-100 which is still sort of flexible, and a BG65 Sill Gasket. Over this will be wrapped Henry Blueskin taped to Henry CM-100 on the exterior and Intello Plus taped to the sill on the interior. It seems like applying a bead of acoustic sealant around the perimeter is beyond boots and suspenders... it's boots, suspenders and a waistband But maybe I'm missing something? Should I still install some sealant in this assembly to keep a draft out?

Asked By Ethan T ; Climate Zone 5A ; ~6000HDD | Jun 5 18
2 Answers

Specific low-VOC sealing around slab floor plumbing penetrations?

I have built my slab-on-grade house with various plumbing penetration that now I need to air-seal. All of these are in the proper conditioned space of the house so low VOCs solution is a must.

Such PVC verticals as drains, radon vent, and pvc sleeves were first wrapped with 'sill sealer' foam to be sure they did not adhere directly to the concrete during the pour.

Asked By Kenneth Gartner | Jun 1 18
7 Answers

Exterior insulation vs. closed-cell spray foam

My project is a major remodel (replacing foundation, moving walls and stairs) in a 2 story 2300 sq ft house in climate zone 3c, zip code 95060. I just received a building permit, and I start construction on July 1, acting as an owner-builder.

House has 2x4 walls and 2x6 roof rafters, all vaulted ceilings. My design calls for exterior sheet insulation (mineral wool) on the walls and roof deck (1.5" on walls, 3" on roof), then cavity insulation in between the studs (dense pack or OCSPF), unvented ceiling. Air/water barrier on sheathing, then furring strips to support wall cladding.

Asked By Phil Boutelle | May 29 18
10 Answers

Insulating Wall Between two Different Slab Elevations

I have a basement with 2 different slab elevations with 2' differential between the two. There will be a stair with 3 risers connecting them. I am insulating the basement from the inside. We are getting ready to pour the slab next week and in preparation I have placed 4" of EPS on top of the sub-slab stone. I am trying to decide how to best insulate the concrete wall between the 2 elevations where the stair will be.

Asked By Jonathan Lawrence CZ 4A New Jersey | May 24 18
4 Answers

Vaulted / Cathedral Ceiling -- Unvented

Hi, I'm in the process of building a cabin near Saskatoon, Saskatchewan, Canada. I can't tell for sure since the climate zone map is for the US only, but I'm guessing this would be equivalent to Zone 6B or 7B.

Asked By User-7075735 | May 23 18
12 Answers

Exterior Insulation on Cinder Block Walls

I have been through many articles talking about exterior insulation techniques, and insulating the exterior of foundations. My house is a little unique, and I'm hoping that someone can offer some insights/guidelines on how to handle things.

Asked By Jameson Taylor | May 18 18
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