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0 Answers

HVAC contractor

Looking for a residential HVAC contractor in Boston that knows high-performance systems. Ideally it would be a company that has an in-house mechanical engineer.

Thanks

In Mechanicals | Asked By Aaron Yankauskas | Mar 26 13
2 Answers

Insulating attic trusses for storage only

I just read your blog on roofing rules. I need the storage space so I am going with room in attic trusses. I am just going to use the space for storage.

In General questions | Asked By Tim Dunham | Mar 25 13
3 Answers

Damp spray insulation voids

Looking for some advice.

I recently had my walls damp sprayed with cellulose. Upon checking everything out after they left, I noticed some voids (or dimples) in the installation where the cavity wasn't quite filled. They are between .5 to 1 inch deep by maybe a square foot. Not a big deal in terms of r value (stud cavities are true 6"), but I had a couple questions:

Is this to be expected? Some part of me imagined these cavities should have all been 100% full, as it doesn't seem it would be hard to overload them as the scrubber takes care of the rest.

In Green building techniques | Asked By Ryan W. | Mar 24 13
3 Answers

Choice of caulks/sealants?

I know there's a completely bewildering array of caulks, adhesives,
sealants, etc out there on the market but I'm kind of interested
in what the building community prefers these days, and why. I'm
not even sure it's 100% kosher to do brand comparisons here on GBA
but if it's all in the context of *opinions* and real-life
experience, hopefully that's okay.

HD seems to sell more "contractor bulk packs" of certain caulks than
others, notably Alex Plus and Dynaflex 230 and maybe various types of
Liquid Nails. I've used all of these in some small ways but not

In Green products and materials | Asked By Hobbit _ | Mar 23 13
3 Answers

What kind of insulation board should I use?

I Live in a cold Climate 6A. I live in a cape style house with 2x4 Knee walls, that have batt insulation falling down on the unconditioned side. I want to put insulation board as an air barrier and to add R-value. What kind of insulation board do you recommend and what thickness?
Thanks,
Mark

In General questions | Asked By Mark Brown | Mar 24 13
3 Answers

How do I contain acoustical sealant toxity?

Acoustical sealant was applied to tu-tuff as the vapor barrier for our crawl space.
This was phase one before going to phase two which would be use the supply and return
air sources to ventilate the area. The sealant was only used to adhere the vb to the concrete foundation wall. The sealant is superior becomes it does not dry out; hence, it maintains a seal
for radon remediation as well as a vb.

In Green building techniques | Asked By william phillips | Mar 23 13
14 Answers

Heating load vs. electrical load ... all ends up as heat anyway?

Would like to debate about the fact that most ( read all ) of our electrical energy usage ends up as heat during heating season, and thus cannot be accounted as for seperate expanses from the heating loads.

I read alot about watching all small electrical loads from mini appliances, chargers etc..
Water tank standy heat losses .. computer let turned on all day long.

But during heating seaons, doesn't it all gets convereted to heat at the end ??

In General questions | Asked By Jin Kazama | Mar 22 13
14 Answers

Suggestions to control Thermal Bridging?

Many times the reading that I do on this site begins to make me a bit woozy,so I thought I might type a question to clear my head,ha!

My questions are regarding a 2x4 wood frame wall and a 2x10 cathedral ceiling with asphalt shingles above.,drywall as the inside finish.

I will insulate the walls and the ceiling with either fiberglass batts or blown cellulose.I am opposed to spray foam,as I know these assemblies are basically unusable and unrecyclable in the future.

In Energy efficiency and durability | Asked By Dennis Dipswitch | Mar 20 13
1 Answer

Reclaimed Iso/Strapping/Sheeting/Shingles?

Hi there, I was trying to piece together an answer by reading already posted questions, but I thought I should just start a new thread. What I want to do:
Strip the two layers of old and failing shingles, check the existing sheathing, replace anything that needs replacing, cover the roof with 3" (maybe) reclaimed Iso insulation, strap that, sheath it, shingle it.

My concerns:
If I go with reclaimed I so I am concerned about nail holes and such. I have been wondering if I should cover the insulation with a breathable house wrap, then proceed with the rest of the roof structure?

In General questions | Asked By Alfred Dedam | Mar 23 13
3 Answers

Ventilation ducts in exterior walls

I'll need some form of duct to get fresh outside air to my ERV and another to dump the exhaust..
I'm building with double stud walls insulated to r40 whole wall. The ERV will be in the basement. I have a place where I can in effect move the walls inward so the duct will be outside the insulation as it crosses the sub floor. Is there any reason to use insulated duct? Would a rectangular duct made of fiberglass "duct board" work? Any reason to not use galvanized steel 'sheet metal' duct sections?

In Energy efficiency and durability | Asked By Jerry Liebler | Mar 22 13
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