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2 Answers

Single-story house in northwest Montana

Hello. I am preparing to build a single-story house for my wife and I in northwest Montana. At this point I am considering a block foundation with a slab as opposed to a crawl space. Would I insulate the inside of the foundation so the outside of the framed...?

Building structure questions.

Asked By Mike Koness | Jul 3 18
5 Answers

Using Closed Cell Foam in Unvented Attic

About to contract for our new home in mountains of Western NC - lots of rain and wind. Concerned about insulation of attic/roof. Avoiding the risks of open cell foam on underside of sheathing discussed on GBA, plan to use closed cell foam (unvented space). Roofing is an architectural asphalt shingle over Zip sheathing/WRB. Local Energy Rater advised to use an additional ice and water shield over entire roof. Concerned about creating moisture trap with this approach. What do the experts recommend?

Asked By user-7048155 | Jul 2 18
1 Answer

Drywall attic air vent baffles?

Any reason not to use extra drywall for attic air vent baffles? It would be installed similarly to rigid insulation or plywood baffles. Sister a 2x2 along the rafter and screw drywall in place. I would eventually insulate under the drywall baffle. Just thinking if there was a way to avoid the landfill with all of the extra scrap.

Asked By Seth Holmen | Jun 30 18
2 Answers

Deep energy retrofit

I'm in St. John's, Newfoundland and Labrador, climate zone 6, about 4800 he'd, wind driven rain category is Extreme. House is 25 years old and wall structure is from inside to outside
1. 1/2" gyproc
2. Super 6 mil poly, acoustic sealant
3. 2x6@24"oc studs, r20 fibreglass baths
4. T&g board something
5. Tyvek
6. Vinyl siding

Electric baseboard heat, HRV ducted to every room, r32 cellulose in a vented attic.

Asked By Steve M | Jun 30 18
1 Answer

EcoSeal in attic?

I'm trying to build as efficient of a house as I can on my budget and I've been watching Mike Guertin's videos on attic sealing. Would eco seal in the attic be worth the $2,000 cost? Here is a link showing what I'm talking about . Additionally I'm trying to decide if I should have the exterior framing sprayed with the stuff or if it's overkill. We are already using zip wall with liquid flas followed by 2" of mineral wool? Additionally I will have a good gasket on the sill plate and 18" base flashing over concrete/zip. Would the eco seal be overkill?

Asked By User-7088022 | Jun 29 18
7 Answers

Minisplit: Leave it on or turn it off?

Very well insulated home. Nudura ICF Walls (2.5" EPS x 6" concrete x 2.5" EPS) with R-40 roof, 3" slab insulation, R7 windows, Zone 4 climate at 5,000 feet elevation. Under 800 sqft of conditioned space and I have a 1 ton ductless Mitsubishi mini-split heat pump (23 SEER).

At 7am the interior temp is 68F and by 6PM the interior temp is 74F. Outside temps in the 92F-98F during the day with a blazing desert sun. .

Should I leave the unit off and turn it back on around 6PM to cool the house down or just leave it on all day? Which is more efficient?

Asked By Peter L | Jun 28 18
1 Answer

How do I properly insulate and vent a cathedral ceiling in Middle Tennessee?

I’ve read numerous articles on here, alas I’m just confused by what exactly I need for my area. Initially, a contractor friend told me to install R-30 insulation rolls, baffles, and 6-mil poly (vapor barrier). However, this seems to not be the proper method based on what I read. Could someone provide me specifics for what is needed for my zone? One BIG note, I’m doing T&G. Was told to attach to rafters (with vapor barrier in between).

Another issue I have is that I do not have soffit vent between every rafter (only about 15-20%).

Asked By austinbecton | Jun 27 18
4 Answers

One layer of exterior foam in climate zone 5

I'm sourcing materials for a project in the Seacoast area of New Hampshire.

I'd planned on standard 2x6 construction with an engineered roof. My intention was 2 layers of 2" foam on the walls (not too partial to type of foam) and 6" of foam on the roof. Cavity insulation of some sort, cost dependent. I'd even be OK with 2x4 construction for a total all R value somewhere around R30. I'm building this house to sell.

Asked By Chris Magness | Jun 27 18
5 Answers

Best unvented shop ceiling option

I’m building my metal roofed work shop in climate zone C4. Because of the pole barn and shed roof purlins I won’t be able to vent the ceiling assembly. I’m planning on using spray foam directly against the underside of my roof sheathing because if this. I have a choice of either using 3” of spray foam or for less money, I can use 2” of spray foam and a R13 fiberglass bat. Which is best? Code for living space in our area in a ceiling is at least 3” of spray foam, but this is a shop and the 2” plus bat option is cheaper and has a higher overall R value.

Asked By Kail Zuschlag | Jun 26 18
8 Answers

What size minisplit and where should I put it?

Hello everyone! I’m building a new home for my new family beginning next month. The home will be 2000 sq. ft., with 2x6 walls wrapped with 1” Dow board on the exterior with R-19 batt insulation. Also the entire house will be sealed with silicone, Great Stuff, and tape. The attic will have R-50-60 blown-in fiberglass and the house will be built on a concrete slab foundation.

My question today is: where should I mount my minisplit heads, how many should I have, and how big should my units be? Thank you all so much!

Asked By Dillonf | Jun 26 18
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