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2 Answers

Understanding HRV Energy Use Calculations

I am trying to understand the last column on the below sheet. I can see that the "last but one" column value is arrived at by subtracting the "Total Annual Energy Use (KWh @ COP 1.0)" from "Recovered Heating Energy (KWh/yr)". But I am trying to figure out how the last column values are being arrived at and also what the last 2 columns mean in layman terms. Thanks.

https://www.portlandoregon.gov/bds/appeals/index.cfm?action=getfile&appe...

Asked By Venkat Y | May 27 17
5 Answers

How does someone cancel subscription when there seems to be no way out??

Could someone guide me in the cancellation of membership? it doesn't seem like it is possible to do so.

Thank you

Asked By James Someone | May 27 17
1 Answer

Tapes for air sealing between concrete and foam or wood/OSB

Looking for some suggestions on type/brand of tape to use, or whether these applications are even feasible or recommended ....

We have several details where I'm considering using a tape to air seal between concrete and another substrate - wood, OSB, foil facing, polyiso foam, possibly also canned spray foam.

Asked By William Costello | May 27 17
0 Answers

Adding an addition after AirKrete and polyiso - now what?

1960's ranch near Rochester, NY

A couple of years ago, the home was resided with vinyl. I took this opportunity to have the home wrapped in Tyvek and covered in 1.5" reclaimed polyiso with black kraft facing. The walls, which had minimal fiberglass insulation, were filled with AirKrete.

Overall this has performed well, the home is quiet and the walls are warm in winter and comfortable - despite problems with the local contractor.

Now I am looking to add an addition, 10x20. The addition will bump out one wall and require part of another to be modified.

Asked By J Heckmann | May 27 17
0 Answers

How do I get Comcast through my envelope prior to blower door test?

In anticipation of a blower door test, water, sewer, electricity, and gas were run to house with one phone call each. Can anyone suggest a way to convince Comcast to provide a stub-out to new construction with studs not yet covered?

Three weeks and half a dozen phone calls (each one requiring a half hour just to get to someone who could look at the job ticket) I usually get: “T.V. has to be ready to hook up before we can install service.” Why, I ask, can you not bring the cable to a utility box and test the signal there? Yesterday I learned this:

Asked By David McNeely | May 27 17
3 Answers

Insulating an attic-based minisplit indoor unit & ductwork

Our home has a newly installed Mitsubishi ducted minisplit. There are now two ducted units in the attic: both the "Concealed Slim Duct" SEZ-KD12NA (there is a 3rd unit within the conditioned space that I'm less worried about). After a long-fought battle with my wife, the indoor units were installed in our attic. I know doing this was dumb but aesthetics won out over efficiency. I've posted on this forum separately about moving the conditioned space to the roof rafters. $60K bids basically killed that idea, at least for now. Right now I just want to band-aid the problem.

Asked By Brian Gray | May 26 17
3 Answers

How can I effectively resolve an issue of next door neighbor's cigarette smoke seeping into my apartment?

My neighbor's door is perpendicular to mine and about 8 inches from mine. Our apartments, long ago, used to be one big apartment before it was divided into two. One of my walls, that was used to divide the once larger apartment, is adjacent to my neighbors. I have lived here 38 years and would hate to move because of some smokers who have moved in next to me. I have asthma and my children seem to be developing it as well. By the way, I have four high-end air purifiers but they are noisy and dramatically run up my electric bill. Please help.

Asked By user-6855474 | May 26 17
1 Answer

Vapor Barrier when using Excel II as Air Barrier

We're retrofitting a bungalow in Toronto, we're using Excel II as an air barrier. We want a green product for a vapor barrier. What's the best product? Would it make sense to use a Blueskin VP as a house wrap?

Asked By Thomas Kaempfen | May 27 17
2 Answers

Hot dormer: radiant barrier time?

I have read Martin's "Radiant Barriers: A Solution in Search of a Problem"
http://www.greenbuildingadvisor.com/blogs/dept/musings/radiant-barriers-...

I have an existing house, about two years old. The second story is made up of two dormers, a bathroom, a "bonus room," and some "usable" attic space (outside building envelope).

The second story gets much hotter than downstairs (8-10 degrees in hot days). I'm interested in whether there's anything we can do to address that, short of cranking the hvac.

Asked By Maurice A | May 27 17
7 Answers

Retrofitting garage to a heated shop - slab and wall details

Hi all.

I am soon to be owner of a house with an attached garage, roughly 20x30. I would like to convert the garage to a heated wood shop.

I am in climate zone 6A (Maine). I will have consistent heat in the shop, probably in the 55 degree range, bringing it up to 60-64 for working temp. I am leaning towards heat pump as heat source.

The garage is a concrete slab, the details of the footings/stems I do not yet know however.

The structure is 2x4 studs sheathed with (I believe) T1-11 exterior ply. Roof trusses (not raised heel). Stud bays currently open to inside.

Asked By Tyler Keniston | May 25 17
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