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1 Answer

Minisplit vs direct-vent gas heater

Lots of stuff about minisplits in the blogs; I'm wondering are direct vent gas heaters are cheaper to install? more expensive to run? My interest is theoretical, but I live in Vt. so AC is not an issue.

In Mechanicals | Asked By william goodwin | Jan 26 13
4 Answers

How do you control outside air condensing on cold building members within a ventilated cathedral ceiling chase?

I am constructing a detached garage with an insulated second story area enclosed within the roof framing. There is a 1-1/2 inch vent chase framed within 2 x 10 roof rafters spaced 24 inches OC. on a 10 in 12 pitched roof. The roof 5/8 inch plywood with composition shingle. Two layers of 2 inch thick foil face, closed cell insulation encloses the lower side of the chase resulting in an R 28 section. I plan to add an additional layer of R 15 rockwool beneath the closed cell insulation. There is a continuous eave vent and ridge vent.

In General questions | Asked By Bob Bishop | Jan 25 13
21 Answers

Energy inefficient Japanese walls - am I missing something?

I am from Connecticut but am about to build a house in a climate zone 4A section of Japan. I have talked with several Japanese builders and am concerned about the energy efficiency of their building envelope design. Before abandoning local practices, I would like to read GBA readers' opinions to help decide if my concerns are well-founded.

In Energy efficiency and durability | Asked By Eric Matsuzawa | Jan 24 13
0 Answers

Salutations! I am building an aquaponics greenhouse and am wondering what anti-mold/anti-fungal to use?

I am building a greenhouse to house an aquaponics system in a northwest climate, and am wanting to use as environmentally friendly anti-mold as possible. I am constructing the main portion of the frame and windows using cedar and polycarbonate and am thinking of using either Fiberlock sealant or OSMO wood finish. Any thoughts? Thank you sincerely, much gratitude.

In Green products and materials | Asked By Evergreen State College | Jan 26 13
14 Answers

We are trying to maximize wall assembly R-value: Very cold climate in CO

New home construction: 2x6 ext wall with 2" of closed cell spray foam with the additional 3.5" of cellulose or fiberglass batt. I was thinking of going with Dow's SIS panel (1" R5.5), but I am reading from one of Robert Riversong's comments that the impermeability of the SIS panel (Polyiso) is a bad idea for our climate.

In Energy efficiency and durability | Asked By ryan evanczyk | Mar 27 11
2 Answers

Anyone know of a dense pack cellulose course offered near CT?

I'm a remodeler in southeastern CT. I will be building my own house within the next year, and I'm looking for a resource to learn how to install dense pack cellulose.

In GBA Pro help | Asked By Samuel Kilpatrick | Jan 25 13
8 Answers

Is a standard 'Home Slicker - 6 mm' for under wood shingle siding adequate for Cape Cod, MA area ?

There are two types of slickers by Benjamin Obdyk .... the 6mm is perfect for what Iwant to do, but there is also a 10mm which is required by code in certain parts of Canada. Is there a 10mm code requirement for rainscreens in MA ?

In Green products and materials | Asked By CUDJOE KUBUAFOR | Jan 23 13
3 Answers

Deep energy retrofit strategies for uninsulated brick home in Phoenix

I'm looking to perform a deep energy retrofit on my 1947 brick home in Phoenix, AZ, and was hoping to get some feedback from the forum about the most cost-effective and beneficial strategies. The exterior walls are exposed double-wythe brick with 3/4" plaster on the interior. The windows are the original leaky, single-pane, steel casements. The attic is vented with R-38 on the ceiling, and the majority of the ductwork is exposed to the high attic temps.

In Energy efficiency and durability | Asked By Nathan Morey | Jan 25 13
2 Answers

Any value to ceiling insulation when constructing a conditioned attic?

I'm ready for insulation in my retrofit project, zone 3 in North Carolina. The building has 1 1/2" of poly foam on the exterior 2x6 walls, which will be filled with cellulose. The roof deck has 3" of poly, the underside will have 6" of open cell foam sprayed onto the underside of the roof deck. My question: The insulation contractor has suggested that I may want to add 6" of cellulose blown in at the ceiling level. I can see some value here preventing sound from migrating between rooms (common walls will be insulated for sound as well), but is there any thermal benefit to be gained here?

In General questions | Asked By Bill Savoie | Jan 25 13
1 Answer

I have heard a lot of talk about our homes of today not outlasting our 30 year mortgage. I would love to hear more about this topic.

Code built house will not last as long as mortgage.

In Energy efficiency and durability | Asked By terry herndon | Jan 25 13
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