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0 Answers

Looking for an HVAC contractor for a project in Sudbury, MA

Hi Folks,

I am advising on a home renovation in Sudbury, MA. It has become obvious that the structure -- about 20 years old -- was built without thought to airsealing. The resulting home performance problems are likely predictable to GBA readers.

Now, the owners are turning a 3-season sun room into a 4-season room and need help figuring out how to best heat and cool the new space. This project also presents an opportunity to address other related issues.

In Energy efficiency and durability | Asked By c talwalkar | Aug 30 14
3 Answers

Air sealing penetrations

My new house is designed to limit penetrations through the building envelope to as few as possible. Nevertheless, sillcocks, outside electrical receptacles, outside lights, HRV intake/ exhaust, etc. need to be sealed.
Are there methods or products that are more effective than others? How about ease of installation? I've seen photos of tape covering holes and that seems like a pretty clunky solution. I'm probably going to either do much of the airsealing myself, or at least supervise it.
Thanks for any advice.

In Energy efficiency and durability | Asked By stephen sheehy | Aug 29 14
1 Answer

Flash foam and Roxul?

I understand from prior posts there are concerns with the flash foam and fiberglass insulation in terms of moisture vapor.

Would the use of proper barriers and Roxul instead of fiberglass help to abate that concern?

In Energy efficiency and durability | Asked By George Levicki | Aug 29 14
5 Answers

PERSIST + Rainscreen siding issues

I am in the final phase of completing my first PERSIST remodel.
We have installed (2) layers of reclaimed 2" polyiso on the walls (over TYVEK drainwrap) of a 1940's ranch and then strapped with 1x4's using headlock screws. Existing walls were in decent shape in terms of flatness and corners were within an 1/4" of plumb over 10'. So the walls were not perfect but they were pretty good, not bad enough to catch the eye.

In General questions | Asked By Charles Chiampou | Aug 24 14
3 Answers

How would you handle this problem after receiving this response?

Here are the facts about this house first;

In Energy efficiency and durability | Asked By Richard Beyer | Aug 29 14
15 Answers

Best method for infiltration heat loss

I would like to ask the math pros here on how to calculate heat loss from infiltration rates.

I have seen so many different formulas in the last weeks that my head is hurting.

So would like to have a "reliable" formula that could be used in my never-ending expanding excel spreadsheets !

Something with at least a little bit of proven precision, that could be used to effectively get additional heat loss using door blower results or planned target value.

Links or straight formula please :)

In General questions | Asked By Jin Kazama | Aug 25 14
3 Answers

How to deal with an interior vapor barrier on a rigid foam retrofit.

I would like to add foam board to the exterior of my house to beef up the R value. The walls currently are 2x6 with fiberglass batts and plastic sheeting as a vapor barrier between the studs and drywall. Most of the stuff I've seen says you don't want a vapor barrier on the inside so your sheeting can dry to the inside but I haven't found much information on what to do if the vapor barrier is already in place. Thanks!

In General questions | Asked By Jacob Roark | Aug 28 14
1 Answer

Nyle Geyser RE problem

I've seen the Geyser RE mentioned on this forum numerous times, so I am hoping someone can help me troubleshoot my unit. I installed one this summer, connected to a new 80 gallon State electric water heater. It worked for a couple of days and then starting tripping the circuit breaker. It was a 15 amp circuit (I was using a 25' 12 gauge extension cord to reach it which tech support had ok'd beforehand). I thought maybe the combo of a 15 amp circuit and the extension cord was the problem, so I wired a new dedicated 20 amp circuit right next to the unit, but the problem persisted.

In Mechanicals | Asked By austin jamison | Aug 28 14
6 Answers

Cape needs insulation retrofit (with ventilation)

Hi all,

New owner of a 1 1/2 level cape here. Finished upstairs. Zone 5. I'm experienced with home renovations and DIY, but new to Capes.

Trying to bring upstairs environmentals in line with lower level conditioned home temps year round without running the mechanicals 24 /7.

No insulation to speak of. No ventilation. No vapor barrier. Planning to make the attic "outside space".

I've blocked all of the underfloor joist bays, sealed all chases and penetrations, insulated the kneewall hatches very well, etc. This has helped a lot.

Next steps:

In Energy efficiency and durability | Asked By M Welch | Aug 27 14
12 Answers

Are minisplits a good solution for heating (and cooling) a smallish addition to my 85-year-old house?

I'm in zone 4 (NYC suburb) and the original house is a 2 1/2 story wood framed house heated by gas fired one pipe steam. Cooling is from window units. Our addition (currently rough framed and dryed in) is two stories with an 18' x 15' exterior footprint. 3 foot block stem walls make the lower level slightly smaller than the upper. The upper level, which connects to our main floor, will be our new kitchen, and the lower level, which connects to a walkout basement, will be a play/TV room.

In Mechanicals | Asked By mike mcguirk | Aug 25 14
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