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2 Answers

Kitchen Island Hood problem


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?


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
1 Answer

Rigid board insulation on the exterior of sheathing

I have read and continue to read the articles and blogs posted here about how and what to place on the exterior of the sheathing. As soon as I think I have the details worked out, another article points a different direction. My remodel project is a home framed with 2X4 walls and CDX plywood sheathing. Before I replace the windows, I must determine how i will insulate. Living in the Seattle, WA area brings in the issue of high humidity.

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

Attic ventilation

In the article on attic sealing on the Building Science Corporation Site and in a recent Fine homebuilding article, they talk about the pressure that having a ridge vent only (in the attic) can create thus sucking conidtioned air from the house out of the home.

In Energy efficiency and durability | Asked By Julie Herr | Jan 25 12
2 Answers

Condensation in enclosed porch

Every since my father put in a new rooft and months later new windows we have been having problems with a leaky roof. About two years ago, one winter day we noticed that ceiling of our porch was dripping water it literally like it was sweating. Our porch floor would always be wet and slippery. Someone had mentioned to me that it may be condensation. I guess this happens when cold and hot air meet which causes the condensation. Can someone please give me some input?


In General questions | Asked By Maritza Gladstone | Jan 25 12
9 Answers

Exterior Penetrations - Air Sealing - Best Practices

Beyond the big penetrations (like windows and doors and attic hatches), I'd like to hear / see how builders are dealing with the smaller penetrations in the envelope.

Using a can of spray foam is tempting, but I don't think it's necessarily the best choice.

How do you effectively seal these?

* Electrical meter base / service panel conduit

* Exterior receptacles

* Vent stacks

* HVAC line sets

* Ventilation hoods

* Hose bibbs

In Mechanicals | Asked By Daniel Ernst | Dec 5 11
22 Answers

Does the blower door test result conflict with contractor recommendations?

My house is all electric except for a propane cooktop. I had a energy audit done last week. Although I don't have a proposal yet, closed cell insulation at the rim joists (fiberglass batts are there now), venting bathroom exhaust fans to the outside, and adding to the blown insulation in the ceiling (plus installing baffles) will probably be included. The attic area above the bedroom level of the house is not accessible now, so a hatch would need to be cut in a closet ceiling. My reading suggests this is a fairly typical approach.

In Energy efficiency and durability | Asked By Carol Oblas | Jan 25 12
9 Answers

Roofing underlayments

In a truss framed cathedral ceiling with R-60 cellulose and continuous vent channels from soffit to ridge, how important is the permeability of the roof membrane with a charcoal colored asphalt shingle roof?

Location; Western Massachusetts - Climate Zone 5, 7928 HDD

In Energy efficiency and durability | Asked By Jon Wyman | Aug 6 10
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