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6 Answers

Open or closed?

After so many questions on attic humidity problems have come up I second guessing my plan. I going to be using 6.5 inch GAF nail base with almost r30. I was going to spray 5 inches of open cell in the attic to finish off the insulating and to air seal. Now I wonder should I use 3 inches of closed?

In General questions | Asked By Eric Chandler | Jul 9 15
4 Answers

Vapor barrier for floating cork floor

I live in Peoria, Illinois (Zone 5A). I'm installing a floating cork floor over an upstairs plywood subfloor. Nearly every website I see preaches on the importance of using a vapor barrier under floating floors, but I've also seen vehement advice against it. The planks I'm installing have a thin cork layer on the bottom, so I really shouldn't use a vapor barrier right?

In GBA Pro help | Asked By Yvette Richey | Jul 9 15
2 Answers

Condensation above ceiling when you live in the attic?

I moved into a New York City two floor house. The "third" floor is really a conditioned, finished attic, which is now a master bedroom. The walls and ceiling in the attic are covered in painted sheetrock. I suspect that there is insulation behind all of the sheetrock, because in the slanted side rooms of the attic (where there is no sheetrock), which are like crawlspace storage rooms, I do see insulation with foil backing. So, hopefully the same exists above the ceiling sheetrock too.

In General questions | Asked By Yonah Levant | Jul 9 15
9 Answers

Buy a dehumidifier or create a register in the return and supply plenums in a damp basement?

I have a 1200 sq ft basement. 1/3 of it is crawlspace under an addition to the house with two former basement windows connecting it to the rest of the full height basement. I have insulated the walls in the basement and crawlspace is covered all the way to rim joist with 20mil reinforced poly to reduce radon.

Yesterday I was inspecting the crawlspace and found dew on poly in the lowest parts of the crawlspace. I do monitor moisture in both crawlspace and basement and we are lately at 78%.

In General questions | Asked By Apollo S | Jul 9 15
8 Answers

Recirculating range hood?

If I'm building an air tight home, should I be looking to vent my kitchen exhaust via the range hood directly to the outside or should I get a recirculating range hood and let the HRV system take care of excess humidity, etc

In General questions | Asked By Steve Babcock | Jul 8 15
8 Answers

Can you recommend a Passivhaus or LEED-certified modular builder in the New Jersey area?

I am interested in having a net zero modular home built in the new jersey shore area. I would love a home built to passivhaus standards but would settle for leed or some other ultra efficient modular home builders. I cant seem to locate anyone on the internet. can you point me to a reputable company?

In General questions | Asked By Robert Medoro | Jun 9 15
9 Answers

Loose-fill cellulose in a small attic

It seems that the best way to insulate the vented attic on my 20x48 new house with a simple 4:12 gable roof will be to blow in loose-fill cellulose, but I wonder about maneuvering within the tiny spaces of the attic. The roof will be framed with standard trusses, with a flat drywall ceiling attached to their underside. The attic will not be used for storage or anything else. The house is in Climate Zone 2B in the Southwest.

In Green building techniques | Asked By Jeff Cooper | Jul 4 15
3 Answers

Recap: Insulate shop with polyiso between rafters

(Removed from an old thread with a similar title -- I decided to repost this as a separate question)

I am back working on my shop. To recap, it's a small 12' x 20' detached shop, in Mass., vaulted ceiling, well-vented at ridge and soffit, using 2" cut-and-cobble polyiso installed below plastic vent channels in each rafter bay, it's a low ceiling with no room to put the polyiso below the rafters.

In General questions | Asked By Tom R | Jul 7 15
5 Answers

Window Screens

I have windows that face southwest. They are not low E windows, I like the warmth they provide in the winter but detest the heat gain in the summer. Is there a screen that would be as good as (if not better than) replacing with a low e window?

So the question is, are there screens that are as good if not better than low-e coatings? Has there been any testing of the screens to support it?

For the kitchen, it opens to my deck and I was thinking of adding an awing that could be used in the summer but allow the sun in the winter.

In General questions | Asked By Robert Hronek | Jun 23 12
7 Answers

Dense-packed cellulose in exterior walls

I have a 100+ year old home and there is currently no insulation in the walls. There is vinyl siding on the exterior and I think it was installed over the old wood siding. I am considering having dense-packed cellulose blown into my 2x4 exterior walls. Am I going to have a moisture problem if I do so? I've read conflicting opinions. I would appreciate any advice you can offer.

In Energy efficiency and durability | Asked By T S | Jul 2 15
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