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4 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
9 Answers

More berm or more insulation?

Currently I am finishing up a design of a house that I want to build this spring. The way the house is designed necessitates it being bermed up with earth on the north side a couple of feet more than the south side of the house. So I have the option to either add more concrete to the north side, berming it up an additional two feet ( to make a 4ft berm) or just building my stud walls and insulating with dense pack or spray on cellulose (I haven't decided yet which).

In Green building techniques | Asked By Jeremy DuCheny | Feb 25 15
3 Answers

Can R-10 XPS foam against concrete and R-15 mineral wool batts between framing be combined in a basement?

I'm in the process of finalizing the plans for my basement. Our current plan is to do R-10 XPS attached to the concrete blocks walls, followed by R-15 mineral wool batts between the studs. I live in central NJ, and the foundation wall is more than 60% above grade.

I'm now concerned about condensation between the mineral wool and foam. Allowing (extremely generously) R-5 for the concrete block, the foam + block is R-15 total.

In Plans Review | Asked By David Pfeffer | Feb 26 15
1 Answer

What will fill in a gap between the porch frame and siding?

building screened porch on mobile home, where the frame is up against the home has gaps because of the siding. The insects will be able to come in. what can be put in there to seal it?

In General questions | Asked By Cindy Bergaus | Feb 27 15
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.
Randy

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
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
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
7 Answers

Any good entry doors out there yet?

Hi,

We're almost done with our Minneapolis energy retrofit, but I still haven't come up with any good entry and side door options. The home is framed with 2x4" walls, and there is also limited side to side clearance to add a more substantial European frame.

In Green products and materials | Asked By Ryan Griffin | Feb 25 15
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