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3 Answers

Is Enviro-Dri WRB a good choice in Silverdale, WA?

I am building a new home, without a basement, on a slope in Silverdale Washington.

Is Tremco Enviro-Dri WRB a good choice for the exterior walls?

What are possible problems with it?

E.g. is mold more iikely? (I could tell from the discussion here of a homeowner with mold in the basement whether that situation is associated to the enviro-dri system or something else.)

In General questions | Asked By Roy Smith | Sep 21 12
14 Answers

Vent space when using polyiso

My rafters are 2 x 8, I don't want to use spray foam, and I can't get a high enough R value using cellulose or fiberglass without furring out the rafters (which we really don't want to do due to limited headspace), so my plan is to use layers of polyiso between the rafters in the cathedral ceiling in the attic room I am finishing off. There is room for me to leave an air gap of at least an inch between the roof deck and the polyiso so I get a vent channel connecting the ridge vent (above the collar tie) to the soffit (behind the knee wall).

In General questions | Asked By Rob Silbajoris | Sep 20 12
2 Answers

Adding R-value to existing attic - Zone 5A

I am looking for suggestions to add R-value to the roof insulation in the single room occupancy apartment building shown in the attached photos. Prior to my site visit, I assumed the roof was flat or low slope. It turns out there is an unused attic with 3' poorly insulated knee walls and sloped rafters above with very poorly done fiberglass batts. The attic floor has 7-8" of blown cellulose between joists over air sealed top plates (assumed a maximum possible R-value of 28).

In Green building techniques | Asked By John Rockwell | Sep 24 12
9 Answers

HRV port installation

Can anyone point me to a detail for passing HRV ports through a thickly insulated envelope?

I haven't decided yet whether I will pass the ports through the rim board assembly or the wall above - I'm leaning towards the wall above so as to lift the ports well above the winter snow line.

The manufacturer's installation detail calls for simply passing through a 6" galvanized round duct... but I'm not sure I like this approach.

Another approach I have been considering is to use, say, 6.5" or 7" PVC as a conduit for the 6" galvanized duct, then filling the gap between with one-part foam...

In Mechanicals | Asked By Lucas Durand - 7A | Sep 22 12
4 Answers

Is cellulose an appropriate choice for insulating against board sheathing?

My old house in Pittsburgh, PA has brick veneer walls sheathed with 1x8 boards and covered with what looks like kraft paper on the exterior of the boards (on the brick side). The boards have a gap between them, on average about 6mm, but sometimes as much as a full cm. Wall studs are standard 2x4 cavities and wall covering is plaster and lath.

Is it appropriate to fill these cavities with dense pack cellulose given there are gaps between the boards and the other wall details and my region?

In General questions | Asked By Stephen Horvath | Sep 21 12
20 Answers

Solving issue of frost/moisture on inside of drywall -- Insulators' proposed solution

We have a house that was built in 2008 and has had frost/moisture on the inside of the house where we have a bumpout that contains a bedroom closet, bathroom, and another bedroom closet. Our house is located in region 4A.

We had an energy audit performed and had the auditor investigate the situation. Per his report, "The condensation problems on the west side of your house are incredibly abnormal. We've seen light condensation on walls during cold snaps but never frost on the inside of a wall."

In GBA Pro help | Asked By Brian S. | Dec 21 11
4 Answers

Panasonic ERV for the whole house

The Panasonic WhisperComfort claims it can be used for the whole house.

The 40 cfm rating is plenty for two people in a 1200 sq.ft. house

Has anyone seen a report or have experience that it does the job adequately?

$300 at WalMart makes it pretty compelling

In Mechanicals | Asked By Kevin Dickson, MSME | Sep 19 12
2 Answers

I had the copper pipes leading to the kitchen under the deck sprayed with foam.

I cannot recall if it was open or closed cell spray foam. The reason I had them covered with spray is because the pipes under the deck were exposed to the outside cold air and always in danger of freezing in the winter.

I now plan to add additional mineral wool insulation and cover everything with siding. My concern is whether the foam insulation will be harmful to the copper pipes or the drinking water supply. Your comments will be greatly appreciated.

In General questions | Asked By John NOWIK | Sep 23 12
3 Answers

What is the best synthetic roof underlayment available?

I have seen literally a dozen synthetic roof underlayments for asphalt shingles. The prices are all over the place. Is there a chart or magazine that compares the relative merits of each?

In Green products and materials | Asked By chris gaidrich | Sep 23 12
5 Answers

Ventilate dead space behind kneewalls

I have recently completed my attic renovation. We moved the insulation layer to the roof deck and brough our hvac inside the thermal envelope. We finished the space for an extra room.I now have keewalls on both sides of the room with a triangular space behind them with all the ducting/hvac etc. behind them. I did not provide any registers or returns to this dead space. Should I be concerned that there is no air movement or turnover in this space? I was thinking it might be wise to provide a louver through the kneewalls to allow some air movement.

In General questions | Asked By Rob McKenzie | Sep 19 12
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