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4 Answers

Strange venting and ice dams

I visited an acquaintance's house last night for another "informal
energy audit", as he was complaining of ice dams bad enough to
bring a little bit of water drip into the top of a couple of window
frames. Boston area, zone 5, and our thermal rollercoaster of
the winter we've been having. The house is typical early-nineties
vintage split-level, simple 6-in-12 or thereabouts roofline with
maybe 5 - 6 inches of blown-in fiberglass on the attic ceiling.
Ridge vent most of the way along. The rafter bays have those token
styrofoam vent channel pieces sitting at the eaves but not nearly

In General questions | Asked By Hobbit _ | Feb 28 14
13 Answers

Envelope Renovation in 2A: Part 1- Attic

I'm going to break this down into 2 posts...attic and wall, with the attic/wall intersection here.

Brief background on existing conditions:

1970 2-story home (2500sf) here in Seabrook (SE Houston), a very hot very humid climate in a 110mph windzone

1st floor: 85% brick veneer on 2x4 stud backup and faced fiberglass batt insulation (sheathing/weather barrier unknown)

2nd:floor: is 12" Masonite lap siding attached directly to studs (yes...no sheathing)...again with the fiberglass batts

In Energy efficiency and durability | Asked By Jon Pippert | Feb 27 14
3 Answers

Air Handler (AC only) in the attic

My 1978 Ranch house in Zone 5 (Southern NY) was constructed with the AC Air handler in the attic. He(Heating is gas fired hot water) . I am replacing windows and re-siding - adding 2" of foam to the exterior. There is no good way to move the Air Handler into conditioned space, and I do not want to create a completely unvented attic.

Can I create an insulated unvented "Room" around the Air Handler, and if so, what is the best strategy? And do I remove existing insulation in the ceiling below the Air Handler so "connect" the space to the conditioned interior?
Thanks for any thoughts!

In Energy efficiency and durability | Asked By Mark Rubinsky | Feb 27 14
3 Answers

REMOTE retrofit

I am in the climate zone 4 and I am working on the design phase of a REMOTE retrofit for a 1000sq ft home built in the 1940's. The house is roughly 16x30' and has two levels. The upper level is stick framed - 2x4 with board sheathing. The lower level is an 8" CMU wall. The house is located on a hill and the basement is 8' below grade at the front of the house and walks out to ground level at the rear (along the 18' side of the house).

In Green building techniques | Asked By Charles Chiampou | Feb 27 14
5 Answers

What is the difference between cast iron vs. stainless steel for an electric boiler?

We are installing hydronic concrete slab heating. the slab has already been poured, i thiink the HVAC guy did not use O2-barrier PEX tubing. As i understand it, this means that a cast iron boiler cannot be used. true? how good are the stainless boilers vs cast iron (reliability), what are the pros and cons, which one would you use? Electro seems to come up in my searches, probably a mid-size 34k to 51k BTU/hr seems appropriate. i was surprised to see that they seem cheaper than the cast iron models... but i'm not really sure what features i should be comparing.

In Mechanicals | Asked By bob tong | Feb 21 14
1 Answer

Installing polyiso foil faced foam to inside of exterior wall

I am remodeling a 100+ year old victorian home and would like to add more insulation to the exterior walls.

The current wall construction was:

Original Cedar siding..... 2x4 wall cavity with rock wool insulation...... 1x8 tongue and groove sheathing.... plaster.

The plaster was removed in order to update wiring,,,,etc......

I don't want to destroy the existing exterior siding on the home.

In Energy efficiency and durability | Asked By Paul Dvorak | Feb 27 14
3 Answers

I need to find a consultant

I need to find a consultant qualified to design residential ductwork, air handler, controls for home with active and passive solar. My house location is North East MD. Consultant need not be located in that area. 610-696-3000

In Mechanicals | Asked By ANDY WADE | Feb 27 14
3 Answers

Insulation and poly (non-felt) roof underlayment

I had a late start framing last fall and could not get an asphalt roof down on my deck before freezing and heavy snow. So, I laid a synthetic underlayment down on the deck for the winter. It will soon be time to put a roof down. However, the issue is that the roof is complex with one dead valley, and several rafter bays which will be nearly impossible to vent, as well as five gable ends with outlookers in cathedral applications on the rack ends which will block venting.

In Energy efficiency and durability | Asked By Bob Brown | Feb 26 14
3 Answers

Want an opinion on sealant for cement and health impacts of offgassing

I am looking at sealing the cement slab-on-grade floor and below-grade sections of poured cement walls. Interested in any adverse health impact for living space.

Does anyone have particular product recommendations? I am particularly looking at Enduroseal and would like any opinions about this product from an environmental/health standpoint for living space. The product offers that it penetrates into the concrete to block capillary water movement inward, and has no offgassing.

I'd like to hear from the discriminating minds at Green Building Advisor.


In General questions | Asked By Chris Campbell | Feb 26 14
13 Answers

Still trying to understand why you don't care about trapping vapor under a vapor barrier

Still trying to understand why you don't care about trapping vapor under a vapor barrier if there is vapor constantly pushing up from the earth. Also interested in good sealant.

In General questions | Asked By Chris Campbell | Feb 20 14
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