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3 Answers

A $2,000,000 green home


Environmental Lawyer Spends $2M Building a Home That Meets Green Building Certifications
ABA Journal (09/06/13) Cassens Weiss, Debra

In General questions | Asked By Greg Smith | Sep 16 13
6 Answers

Boiler cycling on and off with a low-flow shower head

Just wondering if anyone has come across this before. I have a Baxi Luna 310 fi modulating boiler for both in-floor heating & domestic hot water (35,000-105,000 Btu). With a low-flow shower head (approx. 6 litres / minute), the shower water goes from hot to cold constantly. I noticed the boiler cycles on and off the same way. The boiler requires a minimum flow rate of 11 litres / minute to prevent it from cycling on and off.

In GBA Pro help | Asked By bert matter | Sep 16 13
3 Answers

HRV flue combination

I notice on the web there are several references to HRV+flue combinations. I've not seen a discussion of that here though.

In concept it seems like it would be very efficient since the very cold incoming air could accept heat more readily than the indoor ambient air of a normal HRV.

A risk seems like possible increase in creosote condensation. I'm wondering though if it might actually be able to detect and slow a flue fire?

In Energy efficiency and durability | Asked By Jason Crawford | Sep 14 13
5 Answers

Insulating well water line on ledgy lot in climate zone 6...

We are building an energy efficient house in north-central NH (climate zone 6a). This question is a bit off topic, but hopefully someone might be able to help. The lot has shallow soil and there's no way we can trench deep enough to get the well water line below the frost line...and it's very likely that in extended sections we'll only be able to dig 1' or so.

We'd like to avoid rock hammering (damage to already poured slab?) or rock trenching because of expense and other reasons. We feel pretty confident that we can protect the line by:
-burying as deep as possible

In General questions | Asked By Brian Post | Sep 16 13
7 Answers

Help with retrofitting Roxul ComfortBoard / ComfortBatt in existing structure


I need help with my basement insulation project. I am very new at this kind of work so please be forgiving.

In Green building techniques | Asked By Guillaume Dumont | Sep 14 13
6 Answers

Mold: inside vs. outside?

I've read various articles about mold. Most of those focus on moisture, humidity, condensation, and temperature differentials, but I've never read one that speaks directly and convincingly to the issue of why we have so many indoor mold problems and so few outdoor mold concerns. Is there something on the outside (sunlight?) that significantly limits it? Is there something _unique_ on the inside that encourages it? Can we bring some of that outside advantage to inside our homes to limit indoor mold concerns?

In Energy efficiency and durability | Asked By Jason Crawford | Sep 14 13
2 Answers

4" or 6" bath fan duct?

Hi all. Sadly, i have another project so i'm going to be pestering you with dumb questions again...

We are installing two panasonic whispergreen, .3 sone, 80 cfm bath fans. they both have relatively short duct runs that exit through the wall. the inlet on the fan can be either 4" or 6" diameter. i understand the fan will operate at 80cfm regardless of the length or diameter of the duct but which diameter is more energy efficient..?

thanks again

In General questions | Asked By erik olofsson | Sep 16 13
1 Answer

Duct leakage

Looking for some suggestions here.

Had my Energy Star 3.0 final last week, and all tests passed expect for the duct leakage to the outside.
The blower door passed at 1.18 @ 50 pac (was pleased with that), and everything else is fine.

In Mechanicals | Asked By Jesse Lizer | Sep 16 13
2 Answers

Encapsulated batt insulation?

Good morning,,i sent a question in the answer category. not awake yet..

Thanks for reply ..removing the 2x4s woud be to much trouble with al the plumbing and electrical laid out already..what's youre opinion on useing R-13 encapsulated batts for the basement exterior walls..i didnt see anything about that approach...if you suggested the encapsulated batt would work,would i need a extra vapor barrier, being it allready has one..if you dont suggest i have to spring for the closed cell spray foam,,also would i need a vapor barrier for the foam spray
i believe i read it is not needed..thnks

In General questions | Asked By jerry pignato | Sep 15 13
34 Answers

Outside air for woodstove

Been woodstove shopping lately and noticed that "outside air" for woodstoves is done in a couple of different ways. The European stoves in general do not seem to have a direct connection for the outside air duct--it's what the salespeople are calling "proximity" air, meaning a 3" duct from outside terminates very close to the stove, but does not connect. The American stoves are much more likely to have a direct connection. To me, a direct connection makes perfect sense, whereas the "proximity" air looks like an air leak.

What's your experience with this?

In Mechanicals | Asked By David Meiland | Dec 5 11
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