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2 Answers

Vetting a ductless minisplit contractor

I have been doing extensive research on Ductless units and feel pretty comfortable with what I have for my design. One of the things that perplexes me is that the manufacturers won't really warranty their units if you purchase them and install them yourself.

In Mechanicals | Asked By John Brown | Sep 11 17
13 Answers

How can I stop mold from growing on my A-frame ceiling?

I have a problem with warm moist air accumulating at the peak of the ceiling of my A-frame vacation home during summer afternoons. This condenses on the surface of that T&G pine ceiling causing mold to grow. This occurs on days that our windows are wide open as well as during our absence when they are closed. If I aim a fan at the ceiling throughout the afternoon, the problem doesn't occur.

In General questions | Asked By user-6914891 | Sep 8 17
3 Answers

Kneewall insulation in Climate Zone 3A

New construction Zone 3A - mixed humid

I am following the recommendations in "Building America Special Research Project: High R-Value Enclosures for High Performance Residential Buildings in All Climate Zones" (an excellent resource!), but don't see any mention of kneewalls. Should I treat them as a wall (R-20) or attic (R-50)? I am thinking the former, but want to be sure.

In Energy efficiency and durability | Asked By Norman Bunn | Sep 10 17
4 Answers

Basement insulation

I'm looking at a new house design in the SF Bay Area, and am not quite sure how to insulate basement walls. The lot is sloped, so the basement on the left has soil outside the concrete, however the dashed line in the lower right shows the garage door which sees daylight.

The idea is insulate the inside of the exterior concrete walls, similar to what is shown in Slab Happy:


In Green building techniques | Asked By Elfo | Sep 9 17
4 Answers

Infinite R phase change materials

I am looking into using phase change materials in my new home to reduce temperature variability. It looks like National Gypsum's use of BASF's Micronal PCMs in its Thermacore drywall has never gotten off the ground.

I found Infiinite R via Google, but can't seem to find any independent reviews.

Does any one have any insight on this product or viable PCMs?


Climate Zone 3A - Upstate SC

In Energy efficiency and durability | Asked By Pnjfksx | Apr 23 17
11 Answers

Height of (SmartSide) wall sheathing with 12" rimboard?

My basic question is whether to use 8' sheathing/siding panels that barely cover the height of my exterior walls or much more expensive 9' panels that extend down over most of my rimboard.

My single-story 20x48 house is in central Arizona where we have a Wind Design Speed:of 90 mph – Exposure C and a Seismic Design Category: C, The 8' walls are framed 16" oc with 2x4s making up the outer half of a double wall. The walls rest on an OSB subfloor that rests on a 12" rimboard and i-joists supported by a 2x6 sill plate atop a 30" masonry stem wall.

In General questions | Asked By Jeff Cooper | Sep 5 17
5 Answers

What is the best wall assembly for a Zone 6a retrofit?

Interior only, 2x4 studs, 15# felt on the inside of 2x6 T&G sheathing, wood and brick exterior, WRB unknown. Need to devise a retrofit strategy.

In Energy efficiency and durability | Asked By Peter Anderson | Sep 5 17
8 Answers

Which long screws are really necessary?


So I know an engineer should confirm everything, and are useful in most cases ,but lets see if I can get cheaper advise and experience form others. (I have paid for numerous other required Eng. stamps).

Also this is a storage/work shop so I am not as concerned.

I'm looking for best bang for the dollar(LIKE EVERYONE) in a 6" screw for holding my horizontal furring strips on the walls. I'm in Ontario Canada, so less choice of stores willing to ship.

Wall inside -out
2 x 6 stud wall @ 16" OC.
7/16 OSB sheathing
3" Polyiso

In Green building techniques | Asked By Dave B | Sep 9 17
17 Answers

Foundation flashing detail

We are in Minnesota (Zone 6a). 2200 sq/ft single level, slab on grade, with a 1700 sq/ft/ shop.

My 10" double stud wall will cantilever 4" to sit flush with the 4" of perimeter foundation foam. I can flash the connection between the bottom plate and protect the foundation insulation all in one shot.

I attached a quick sketched detail of what I plan to do. I'll just buy rolls of painted aluminum and nail it through the plywood sheathing into the studs and backfill. Then the WRB will lap over the top of the flashing above grade, rain screen battens and then siding.

In General questions | Asked By Scott K | Sep 5 17
6 Answers

Best layout/ideas to build on a lot in Phoenix with a west-facing backyard?

Anyone have any ideas or advice on laying out a home on a lot where the backyard faces west?
To add to that issue, the land is located in the Phoenix area. I attached 2 pics of parcel in google earth.

In General questions | Asked By Greg Grigutis | Sep 8 17
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