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1 Answer

Anyone tried HomeSEED yet?

Just saw this yesterday. Looks like an interesting way to explore alternative strategies to meet energy goals.


In General questions | Asked By Larry Burks | Feb 3 12
12 Answers

Rigid Foam on the interior face?


I am working on plans for a new house and have been looking at a couple of options for the exterior wall assembly. Climate zone 5, coastal, very humid summers. Will probably be forced air heat and central AC for cooling.

Looking for approx. R-40 walls.

I am leaning towards a double 2x4 stud wall filled full with cellulose. I prefer the environmental benefits of cellulose over spray foam and rigid foam. It also seems like detailing/ flashing at windows/ doors etc are much easier with a double stud wall than rigid foam on the exterior.

In Energy efficiency and durability | Asked By Chris Harris | Feb 2 12
1 Answer

Exterior Rigid Insulation and Siding

I recently completed a single family home in Va with 6" stud walls (cellulose) and exterior rigid insulation. I wanted to have 2" minimum exterior rigid, but the contractor pointed out that the literature on the specified siding (Hardi-Plank) only supported up to 1" rigid insulation. They also did not seem to support a rainscreen detail of any type when rigid insulation was used.

In Green building techniques | Asked By Grayson Jordan | Feb 3 12
0 Answers

A nice TV news report on Alan Gibson's Passivhaus development

Here's a link to an interesting TV news report on Alan Gibson's Passivhaus development in Belfast, Maine:

Congratulations, Alan -- looks good.

In PassivHaus | Asked By Martin Holladay | Feb 3 12
5 Answers

Spotless HVAC filter

Why would my HVAC filter show absolutely no dirt or dust? It fits tightly and there is no residual dust in the air handler unit. A couple of years ago I found that the top of one of the return runs was never closed in, leaving it open to the mechanical room in which that return was located. I covered the opening with duct board and sealed it with mesh and mastic. The majority of returns are panned (what a joke!) and are not accessable. Those that are accessable, I have also sealed appropriately. The filter may not display dust, but the house sure does! Climate Zone 5.

In Mechanicals | Asked By Chris Brown | Feb 2 12
1 Answer

SIP nail board

Can any one tell me the guage of the metal skin on SIPs 4" nailboard?

In Green products and materials | Asked By Bruce Glanville | Feb 2 12
9 Answers

Is sprayfoam or rigid foam a logical choice?

I've read a few of the articles on how to properly design an unvented crawlspace, but couldn't quite find something that fit the scenario of the crawlspace under my apartment. So here goes.

I'm currently renting an apartment, while in school, that is located just feet from a small lake. Upon conducting general UA calculations for total heat loss in the building (as a project for a class), I noticed a few things of concern in the crawlspace below the first floor, and am looking for some advice. Allow me to explain the circumstances.

In Energy efficiency and durability | Asked By Mike LaCrosse | Feb 1 12
4 Answers

Window film to reduce SHG from skylight?

A client of mine has a couple of large skylights, about 5'x7', both facing southwest, and they really get cooking when the sun is out, so we're looking for ways to reduce the amount of solar heat coming through them They are low-e2 glass. Options we're considering are (1) reglaze them with lower SHGC glass, (2) install interior "storm" windows below the existing glass, and (3) applying some sort of film to reduce solar heat gain. There appear to be several manufacturers of such films... 3M and SolarGard are a couple.

How well do these work? What are the issues?

In Energy efficiency and durability | Asked By David Meiland | Feb 1 12
0 Answers

Enter your best project in Guild Quality's Green Project Contest

The contest: GuildQuality will feature pictures and brief descriptions of our readers’ best green building projects ... on [the GuildQuality] website, and readers will vote on their favorites.

How to enter: Before February 15, email marketing at guildquality dot com at least one and as many as nine pictures of your company’s best green building project, along with a 50 to 200 word description of the project.

In General questions | Asked By Carl Seville | Feb 1 12
10 Answers

Will building paper over foil faced polyiso negate the radiant barrier?

I'm planning an exterior renovation in S.C. (hot, humid zone 3). I'll be installing 1" of foil faced polyiso on the exterior. I plan to seal the seams, but am considering a belt and suspenders approach to the drainage plane. I don't know that I trust the tapes and sealants to hold up under such extreme conditions, so I'm considering installing a house wrap over the top to allow better flashing integration, especially in the area where a gable roof ties directly into the side of the home.

In Energy efficiency and durability | Asked By J C | Feb 1 12
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