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1 Answer

Solar rebate?

In FINE Homebuilding, May 2014, an article by Bob Ritacco: her list: the cost and rebates on a solar system in NY -- state tax rebate as well as state rebate and Energy star rebate .

My solar system is in Mass. I get a small state credit and can find nothing about the Energy Star rebate on their web site .

Can anyone help me If I'm missing something? Thanks.

In General questions | Asked By Randy Durbin | Feb 26 15
4 Answers

What's the best way to address insufficient foam R-value outside the vapor barrier in Zone 5?

We're in new construction now, and had to put the brakes on due to moisture in the wall assembly. Our wall design meets code for Zone 5 (Illinois), but we want to make sure we never have a problem with mold.

We're using Ox Engineered Products Structural Insulated Sheathing (SIS) 1" polyiso R-5.5 and 2 x 4 stud cavities filled with un-faced mineral wool, Roxul R-15. The Ox SIS (formerly Dow) has a perm rating of 0.3, so its use requires drying to the interior. It is meticulously taped and sealed, so it is also our air barrier. The Roxul is very vapor-open (roughly 30 perms).

In Green building techniques | Asked By Dave Brooks | Feb 25 15
9 Answers

Signs of a properly sized furnace?

The most common theme I see when people talk about oversized furnaces is reduced runtime & short-cycling.

But what does short-cycling mean quantitatively?

a) 5 mins on, 5 mins off, repeat
b) 5 mins on, 10 mins off, repeat
c) 10 mins on, 5 mins off, repeat

According to the Manual J heat load, my furnace is only 5% oversized. When I set the stat to warm up more than a couple degrees, it does take a while (e.g., more than an hour). I've measured almost 100 degrees from my warmest supply register & 68 degrees at that room's return (rise of 32deg).

In General questions | Asked By Jeff Watson | Feb 26 15
3 Answers

I'm converting a barn to a residence

The slab is not insulated, and there are no below-grade details beyond the posts that support the structure. My architect is resistant to insulating on top of the slab. He worries that if I don't leech heat into the soil...

The slab is 64' x 46', and 4" thick. The central section was tapered toward center drains, so we have some leveling to do. We are in zone 5, I believe, and temperatures have recently dropped to -18F, though that is unusually cold. My concerns are comfort as well as avoiding condensation that might degrade floor coverings and encourage mold growth.

In Energy efficiency and durability | Asked By Dean McCracken | Feb 25 15
3 Answers

Passive Radon Mitigation using Solar/Wind Turbine Fan

Here's my dilemma: New home less than 5 years old with passive radon mitigation system that runs up through the house exterior walls. Ceiling is vaulted so there is no attic or way to install a radon fan up there. Got quote to reduce radon and contractor said to cap off the existing pipe and install a new pipe that runs up along the outside wall with an attached fan, essentially abandoning the existing passive system.

In Green building techniques | Asked By Robert McDonald | Feb 26 15
4 Answers

EPS, PolyIso, or Double Stud Wall

I'm doing my research and having quite the controversy between these three options.
Zone 5B - SO I have to worry about hot summers and freezing winters.

In a couple of questions I posted here I learned that EPS is more of the favored child around here while XPS is considered more costly (Agreed) and poorer performance in cool temperatures (I don't know, just going by what I heard)

In Green building techniques | Asked By Nicholas C | Feb 26 15
2 Answers

Insulation question

I have an apartment want to add insulation from the exterior.
It is a block building 1950's vintage. Walls in the inside are stripped with 3/4 furring strip. Insulated with 3/4" fiberglass with vapor barrier on inside. Finished inside with plastered walls.
I am thinking of adding foam sheet insulation to the outside of the building. I do not want to trap in moisture and cause mold problems. .
What is the proper way to do this. I do my own work. If anyone can guide me in the right direction I would appreciate it.

Thank You,

In Green building techniques | Asked By Charles Craig | Feb 24 15
2 Answers

Buying a house and want to make it super efficient. I have some concerns about the attic. Can you help?

I am about to close on a house that was built in 1972. It is in Longview, Texas. It is 2100 sq. ft. The garage was made into living space at an unknown date. Has a 3.5 ton central air unit and electric furnace for heat (inspector said that is too small and likely was in place before the garage was converted). Flex type ducting in the attic. My goal is to eventually do the entire place from top to bottom, as I can afford it, and make it cheap to heat and cool. I have several plans in mind. Insulation of the attic I think will be my first step.

In Energy efficiency and durability | Asked By Sam Vail | Feb 26 15
11 Answers

Recommendation for minisplits vs. gas-fired HVAC for new Massachusetts building

I am building an energy efficient 15 unit apartment building in MA this spring. We can either go natural gas or electric. I am considering going all electric since the MA Energy Code is so stringent and the heat load will be relatively small even though there are very cold temps at times. We might even put on solar panels for the house meter.
The electric units would take up much less space and I would rather not have to put in gas at all. I am not thrilled about electric hot water heaters but understand that the newer tankless units are much better.
Any input would be appreciated.

In Mechanicals | Asked By Bill Perkins | Feb 25 15
4 Answers

What happens to inward drying assemblies after a dozen coats of paint?

I'm just curious what happens to the assemblies after a house has been lived in, repainted, sold repainted, turned into a rental (lots of re painting), etc. you get the idea. I've only read about permeability after a few coats of paint and want to know expert opinion about if this can lead to future disaster.

Also, has anyone measured the permeability of GWB with a covering primer like Kilz that is shellac based?

Finally, how does the permeability of thin veneer plaster compare to level four drywall or skip troweled drywall mud?

In Energy efficiency and durability | Asked By Rick Van Handel | Feb 25 15
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