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1 Answer

Only an inch gap below interior door — is that enough to promote air return in a bedroom with a closed door?

Contractor did not install air return in the bedrooms. There is only one large air return in the hallway.

In Mechanicals | Asked By Fabiano Pita | Dec 28 13
1 Answer

Best recessed lights for insulated ceiling?

I recently moved into a 1 story ranch home. There are preexisting 6" recessed lights in the kitchen and bath (8 total) that I would like to replace with airtight lights. I also like the look of the lights and would like to add more throughout the house. There seems to be a ton of housings and trims out there. Which are the best for your buck? Also, if I have the patience and time, can I just buy the cheapo non IC or airtight lights and build enclosures for each light?

In Energy efficiency and durability | Asked By GEORGE HICKS | Dec 28 13
5 Answers

Can a wood interior be air sealed?

I'm working away at a cottage in southern Ontario, zone 5.
I've been researching all my different plastering/drywall options, and I just had to ask...
Can a wood interior be reasonably air sealed? If one was to use poly vapor barrier behind T&G lumber, wouldnt' it leak like a sieve due to all the fastener penetrations?

Thanks again,

In General questions | Asked By Richard Baumgarten | Dec 26 13
2 Answers

Has anyone had direct experience with a SIPs company for a complete residential project?

I have started a dialog with Premier SIPs (because they are 130 miles close) and with Fischer SiPs because they are very responsive (2400 miles distant) ~ has anyone had experience with either of these companies? The project is a 1500 sf modern studio type guest house (remodel), a shed roof with 16' at the high end. SIPs are planned for all the exterior walls and roof, traditional framing for the few interior walls? Love to hear about your real world experiences.

In Green building techniques | Asked By Caroline Di Diego | Dec 23 13
1 Answer

Edwards valance?

I've recently become aware of an HVAC alternative that distributes heating and cooling without any fans, all hydronic, called the Edwards valance. It sort of resembles hydronic baseboard heat but relocates the "radiators" to the top of the walls and adds a provision to collect condensed moisture when cooling. Has anyone any experience with this system?

In Mechanicals | Asked By Jerry Liebler | Dec 27 13
7 Answers

Air sealing exterior Celotex fiberboard sheathing


We are desiging the residing of our house located in central New York State. The house was built in 1973 with some later additions done by prior owners. We are going to take the opportunity to add air sealing, water management, rigid insulation, a rainscreen, some new windows, then fiber cement lap siding. Planning to DIY it.

My particular question concerns the air sealing. I want to get the house as tight as possible while we have access.

In Energy efficiency and durability | Asked By D H | Dec 22 13
5 Answers

Moisture concerns — Vinyl siding over the top of stucco in Portland, Oregon

I am looking at buying a 1907 duplex in Portland, OR, but have some concerns about the existing wall assembly.

The current owner had vinyl siding installed over the original stucco about 10 or 12 years ago. I'm not wild about stucco to begin with in this climate (Marine), and the fact that the stucco has now been compromised with fasteners for the vinyl siding makes me more concerned. There are no signs of moisture or structural issues that can be seen, but since we do not own the house we can't do the inspections that might really show what's underneath.

In Energy efficiency and durability | Asked By Cyrus Collins | Dec 26 13
5 Answers

Where is soffit venting necessary?

The December issue of Journal of Light Construction has an article featuring building techniques of four high performance builders. Three of the buildings pictured have truss roofs; one of those clearly has a ventilation channel from the soffit to the space above the insulation; one is unclear and one, a certified Passive House, clearly does not. There, the cellulose insulation is against the inside of the roof sheathing for what looks like 2'-3'. So my question is, in a vented attic over a very tight house, when is venting to the soffit necessary?

In Green building techniques | Asked By Bob Irving | Dec 21 13
12 Answers

1929 Brick Building in Zone 5A needs insulation— Half of the low-slope roof is very tight and not accessible

We have a 1929 Brick building in Zone 5A with an 8,000 square foot low slope EPDM Roof. It has old single pane windows with cheap metal storm windows attached. The exterior walls are 13" thick, with 9" of hollow bigger bricks, and 4" of regular nice looking bricks).

The first floor has been renovated already, and now we would like to add apartments to the top floor. Before we do this we would like to make some energy efficiency upgrades. Can you recommend what would be best for insulating the attic and or walls?

North half of attic has room to move around in

In GBA Pro help | Asked By Aaron Hirshberg | Dec 3 13
9 Answers

Is open-cell foam appropriate for spraying the bottom of a roof deck?

We are building in Indianapolis, middle of zone 5. House will be on a slab, under-slab hydronic heat powered by geothermal, 4" Thermocore SIPS walls with 2" of rigid foam on outside of that. Truss roof. My homeowner wants the bottom side of the roof deck sprayed. My experience is typically spraying the attic floor, not the roof deck. However, in this scenario, we will have ductwork in the attic, so it does make sense to spray the roof deck, so the ducts are in conditioned space. My insulator is quoting us 5-1/2" minimum open cell foam.

In Energy efficiency and durability | Asked By Allen Brown | Dec 20 13
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