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12 Answers

Outdoor mini split condenser unit in an insulated ventilated box indoors?

I need to cool (summer) and heat (winter) one room which is total 16.7 x 12.2 x 8.5 feet (1731 cubicfeet) (5.10m x 3.70m x 2.6m). I would need a unit between 2 or 3 tons.

Unfortunately I am not able to install the outside condenser unit outside of the building. That is the reason why I need expert advice.

Asked By purpleAnt | Mar 20 18
10 Answers

Zip or Zip R?

I've been doing a lot of research trying to find the best option for residing by 1920 house located in Climate Zone 4 - mixed-humid. Existing plaster and lathe walls on the interior. I've asked a few questions on this website and the responses have been very helpful so I'm asking one more.

I'm planning to remove the existing vinyl siding and wood clapboards and spray foam the walls from the exterior with medium density spray foam to give the stud cavity an R value of about 21.5.

Asked By Michael Mohr | Jan 24 18
1 Answer

Water heater power consumption monitoring.

I searched but only found one thread from three years ago. The advice then was to use a standard power meter. While the idea is good, the box and meter would take up a large amount of space and wouldn't really give much information about when the power is being used. Does anyone know of a reasonably priced option to monitor a single 240v circuit? Thanks

Asked By Calum Wilde | Mar 22 18
1 Answer

Does interior ceiling strapping cause a moisture issue?

I am in climate zone 6 and am currently concerned about my insulation strategy on
a remodel of a 100 year old kitchen.The customer wants cathedral ceilings so I am trying to do my best

Asked By user-7004305 | Mar 22 18
28 Answers

Taping of Roof Sheathing / Wall to Ceiling Vapor Barriers

We building in climate zone 6A. We have planned unvented cathedral ceilings and we are planning to do 4" (or maybe just 2" depending on cost) of closed cell spray foam applied to the underside of the roof deck. We are then going to net and blow in fiberglass to the remainder of the cavities between the 16" TGI's.

I'm planning on the closed cell foam being my air and vapor barrier on the roof. On the walls the my air barrier will be the taped sheathing and the wall vapor retarder will be latex paint.

Two questions:

Asked By Steve Mackay | Mar 21 18
7 Answers

Wrapping subslab poly over perimeter foam

I am trying to figure out how to connect my subslab poly to Intello air Barrier. As you can see on the attached detail, I am proposing taping the poly to the foam... and the Intello is taped to the sill plate and perhaps the top of the foam. I'm not sure how best to bridge this gap. I know that the foam isn't an air barrier, but I'm not sure how to bridge this gap... perhaps I could use some sort of faced foam at this location?

Asked By Ethan T ; Climate Zone 5A ; ~6000HDD | Mar 21 18
10 Answers

Roof Insulation Approach

I'm building a single story addition and researching roofing insulation options. I'm considering an option where I use 11.5" ijoist rafters with a luan panel nailed to the bottom of the top ijoist flange in each rafter bay creating a vent channel from soffit to ridge. For insulation - total to be R49 - I would install 2" foil-faced polyiso to the underside of the ijoists and foil tape it to create my air barrier. Finally, I would dense-pack cellulose the rafter bays through holes in the polyiso. So I believe I have my air barrier on all sides of the cellulose.

Asked By John Rooney | Mar 15 18
0 Answers

Polyiso Interior Insulation in Old Barn

I am starting on the second floor remodel of a 19th c. barn, and I'm considering using polyiso panels on the interior side. I've never used rigid and non-rigid insulation in conjunction, and I have a few questions.

The Basics:

This will be a storage space and workroom. The barn is in Maine. The barn exterior is original horizontal siding (which I may be replacing but not until summer) over original vertical 1x sheathing (with some gaps). This is attached directly to the frame of the barn, which is open on the inside and roughly 5" deep.

My Plan:

Asked By ThreeBirdFarm | Mar 22 18
3 Answers

Mini Split in 1905 All Brick Home

I’m looking for a bit of help selecting a mini split setup for my historic district 1905 all brick 2 family home. This will be part of a major major gut of part of 2nd floor, so a number of energy improvements are on the docket. We will rent one of the units.

I would like to do ducted mini splits for each unit for aesthetic/historical reasons. I have heat pump water heaters already. This would be the only heat source, so heating loads dominate. Possibly 1 unit for front of each unit, 1 for back.

Asked By twoodson | Mar 22 18
0 Answers

Rockwool (Roxul) sheet sizes. [2' x 4' or 4' x 8']

We're about to start insulating the foundation walls with Rockwool/Roxul Comfortboard IS 80.

In all of my reading I have seen theses boards come as 2' x 4' boards. Even then I have read of some difficulty handling.

Our supplier is suggesting 4' x 8' boards of the same product, but I am worried that this will be even more difficult to work with.

Has anyone here worked with Comfortboard for vertical exterior insulation and have experience witht he 2' x 4' or 4' x 8' board sizes? Any thoughts on the matter?

Asked By Ethan T ; Climate Zone 5A ; ~6000HDD | Mar 22 18
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