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6 Answers

Dipping a big toe in solar

I was wondering if there was a good guesstimate tool for helping to figure out "how much Solar I need"?

I am thinking about adding Solar to a spec. house and was interested in Solar since the price point has dropped so much. I will be doing the panel install myself with my crew and have the electrician wire it up.

In General questions | Asked By leo kloop | Feb 20 15
11 Answers

What is the best sealant to use for airsealing?

I know I want seal as many air paths as possible. Is there one particular sealant that works best for things like drywall to studs, spaces between double studs, rigid foam to studs and PE film?

In PassivHaus | Asked By Donald Lintner | Jul 28 09
12 Answers

EPS or polyiso? Layered, taped seams?

I have found a supplier for EPS (plain EPS, no coatings) or Polyiso (foil faced on one side, white non-reflective on the other side)

1.) The polyiso is double the price. However, it is effectively better at insulating to my knowledge. I assume it should be my pick?

2.) I don't want to use more than 2" of foam on the exterior. With either product, I believe it will be advantageous to layer two 1" thick pieces with staggered joints. If I don't have the time I will simply buy the 2" thick and call that good.

In Green products and materials | Asked By Nicholas C | Feb 22 15
4 Answers

Insulation help needed?

I am in the process of building a house and thought I had a good plan for insulating, but want to know if I can do better. My current method I planned on using will pass code, but i figured if I can increase R-value effectively, why not. Better to do it now. I live in zone 4a. We have hot summers and fairly cold winters.

1 story
2x6 construction
Vinyl siding
Tyvek house wrap
Osb sheathing
Fiberglass or denim batts in stud cavities for R-value of 21.
Drywall
Have a full basement, will be unfinished for awhile.
Attic will have like R 50 blown fiberglass

In Energy efficiency and durability | Asked By Nick Lynn | Feb 21 15
4 Answers

Possible electrical ground out or short?

On the 7th of January, my townhouse electricity started cutting out (around 7 times). There was some wind in the area and cold temperatures, near zero. It stopped and soon after I would get shocked if I touched a lightswitch or my pet's nose. My power usage has doubled, but that may be due to the temperature change. It is my first winter in this place. However in the past, I have never had such a huge increase in usage. It went from 537 kwh to 937 kwh and increased again this bill to 1087 kwh. Could a ground out cause the static buildup? (The floors are carpeted.)

Thanks.

In GBA Pro help | Asked By Sheleen Feldhaus | Feb 21 15
1 Answer

How to properly vent a modfied gambrel roof?

Hi,
My family and I purchased a 2 story modified Gambrel style home 5 years ago. By modified, I mean that the vertical roof sides go all the way to the foundation. So we have sloped interior walls upstairs and downstairs.

In Green building techniques | Asked By Charlie Baxley | Feb 23 15
3 Answers

Article idea?

Perhaps this has been done already but i am interested in an article that lists expected lifetimes of the different building materials, brick (frame and veneer), wood, EPS, XPS, cellulose insulation, fiberglass, drywall, plaster/lath, OSB, roxul, plywood and all the rest (with caveats about what shortens and increases their service life and i'm sure different formulations are available, i see many brick frame buildings in the ares over a century old and its easy to see some are looking very good and some are breaking down).

In Energy efficiency and durability | Asked By Alan B | Feb 23 15
2 Answers

When using a LED conversion kit for a recessed lite, can you fill the can with fiber glass insulation?

I have two lights in a vaulted ceiling that leak air like crazy and make it difficult to keep the room warm. If not is there a better way to insulate the lights without replacing them?

In General questions | Asked By Rick Miller | Feb 21 15
1 Answer

Will "Roof Melt" chemically or physically damage an asphalt roof?

In addition to questions concerning its chemical impact on an asphalt roof, is it effective in reducing the ice and snow on this roof?

In General questions | Asked By JOSEPH POLAND | Feb 21 15
2 Answers

Is there a way to provide geothermal HVAC to a rim joist in order to keep the rim dry?

I have a Rim joist that was just above grade sitting behind a 5" concrete lip ... presently i have waterproofed exterior foundation wall, rock from footing up to sill plate, sill is sitting 6" above grade right now ... though 2 feet out from wall the grade rises 1 ft. I am contemplating ways to run radiant tubing behind the Rim joist and sil plate in order to keep them at a desired emulated ambient temperature, pulling water from geothermal pump, in order to avoid condensation.

In General questions | Asked By Jon R | Feb 19 15
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