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10 Answers

Open-cell foam or cellulose over ceiling?

The ceiling has been dropped 1 foot, and sheet rocked, as well as painted-
1 prime and 2 finish coats.
Tek track lighting and a few cans (IC) have also been installed.
The duct work is in and installed within the 1 foot dropped ceiling.
My question is:
Is it ok to use open cell soy foam directly over the duct work, and over
sheet rock directly? My carpenter is concerned for the expansion of the foam
over the sheet rock, itself, as well as spraying directly on the installed duck work.
I would save money and be able to use blown in cellulose to a depth
of rough;y 15".

In Energy efficiency and durability | Asked By gary scheft | Jan 27 12
25 Answers

Different SIP thicknesses, different shell types, windows.....

Working on a fun home that will get some solar gains and pretty simple design. We plan to make it future PV adaptable when the costs drop some. Looking at a few wall design concepts.

In Green building techniques | Asked By Jesse Lizer | Jan 20 12
1 Answer

Drywall Vapor Retarding Primer in basement

Hello, I'm finishing the basement paying attention to Joe L's detail: http://www.buildingscience.com/documents/digests/bsd-103-understanding-b...
My drywall contractor suggested vapor retarding primer, before he textures, as this is his standard practice.
Question: should we forego the primer and use only the texture and then latex paint?
thank you

In Green building techniques | Asked By Frank O | Jan 27 12
5 Answers

Open cell or Cellulose inside Closed Cell barrier

Hi Everyone,

Looking for a couple opinion answers on a project I am doing. We are going to do 2 inches of closed cell foam inside a new construction home to vapor / air seal it as best as possible, The next step is where im a little stuck.

In Energy efficiency and durability | Asked By Denis Recchia | Jan 27 12
13 Answers

Spraying closed cell spray foam directly to fiberglass batts?

Working on a house in Chattanooga TN (zone 4) that needs weatherization badly. Already decided on cc SPF to seal some "crawlspace walls" and exposed floor system from below that are outside the "crawlspace". There are many angles, transitions and irregularities that would make rigid foam or air barrier protecting batts very difficult hence the reason for going with SPF.

In Energy efficiency and durability | Asked By Brian Knight | Jan 26 12
7 Answers

Can I really use 2" of rigid insulation under fiber cement siding?

I'm an architect in Wisconsin (climate zone 6B) and am planning to build a 300 s.f. addition to my house. I'd like to side it in fiber cement siding to match the existing house. According to my calculations, if I want to use rigid foam insulation on the outside of the 2x6 walls (with R-21 fiberglass in the wall cavities), I need at least R-11.25 in order to avoid condensation on the inside face of the sheathing. I was thinking we could use 2" of polyiso.

In Energy efficiency and durability | Asked By Julie Kardatzke | Jan 26 12
2 Answers

Kitchen Island Hood problem

Hello,

Not sure if I chose the right category to ask this question. I apologize if it’s misplaced.

I installed a kitchen island hood last summer with 6" exhaust duct straight up through the ceiling into the attic and through the roof in a bangalow. Location - Toronto Canada. I assume it's a zone 6. The duct was inside insulated sleeve.
Now that the winter is here and temperature changes sometimes 10 degrees in one day occasionally water is leaking from out of the hood.

In GBA Pro help | Asked By Andrei Sosnovsky | Jan 25 12
3 Answers

What type of polyiso insulation to use over sheathing?

I would like to know what type of polyiso rigid board to use over the exterior of sheathing, assuming a rainshield will be placed over that? Does foil covered improve with radiant heat or does it trap moisture and create mold problems on the sheathing interface as some blog responses claim? Hunter makes H-shield which has fiber reinforced surfaces, but no foil. Would there be deterioration concerns?

Thanks,
Steve

In Energy efficiency and durability | Asked By Steve dorsey | Jan 26 12
1 Answer

Spray foam insulation in rafters above exisisting blown cellulouse in ceiling

Spray foam insulation within roof rafters is proposed for a large town hall building built in 1883. Location is in Northern part of the mitt in Michigan. Attic space is very, very large. Existing insulation consists of 12" blown in insulation in what I believe to be a non- vented attic space
Heating units and ductwork are in the attic. Plans for the future are to move the furnace to the basement and air condition unit to be in the attic. Considerations are also being discussed for an air exchanger, location not known.

In GBA Pro help | Asked By steve miller | Jan 26 12
9 Answers

PV Solar vs. Geo

My wife and I are planning to build a new house (2400 sq. ft) in Southern Delaware. We are considering PV solar and perhaps a closed loop geothermal. Not sure we can afford both. Rebates in DE. appear to be higher for solar than geo. Both technologies would provide credits for Fed tax; no DE state tax credits. In addition, we would receive credits for unused solar production and be able to sell SRECs. Nothing similar for the geo install.

In Energy efficiency and durability | Asked By Ken Niehaus | Jan 25 12
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