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2 Answers

"Pretty good house" window choices

Hi, we are in the design stage of a high efficiency retrofit and addition to an 1888 Victorian house in the Chicago suburbs. Our architect and his preferred builder are leading many of the Passive house projects in the area and are very interested in getting our project to approach those standards. Although i think it would be very cool as well, i am finding that the technical approaches and costs simply don't justify the benefits. In doing my own research, i am leaning towards designing for "pretty good" near net-zero instead of near-passive.

Asked By alok khuntia | Feb 27 15
0 Answers

Foil faced batt insulation affect on wall construction.

I’m in the process of planning energy retrofit for my house located in Philadelphia (zone 4A)
Existing wall construction consists of t1-11 over 2x4 framing with foil-faced batt insulation. The plan is to add 2 layers of 2” polyiso to the exterior taping joints making polyiso my WRB. Is there any concern that moisture trapped in the wall cavity won’t be able to dry to the interior due to foil faced batt insulation?

thanks!

Asked By Michael Kalustov | Feb 27 15
6 Answers

Insulating a low-slope EPDM roof from the ceiling below

Hi. I recently had an Epdm roof installed on my 140 year old house. It's low slope and meets with a gable roof on the other part of the house. The Gable is standing seam. We had a tapered ISO board system installed as the underlayment to help with drainage and make the edge details easier to deal with. I reframed the roof and sheathed it myself before the roofing contractors started so I could save money. At the time the ceilings underneath the roof were all closed so I installed 4 inch rockwool batts right on top of the plaster/lath of the ceilings below.

Asked By joseph moore | Feb 26 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.

Asked By David Pfeffer | Feb 26 15
15 Answers

General questions re: building in Zone 7

Long time reader, first question...(I apologize in advance for length).

I will be building in the next year or so, this is my 5th home I have had built and have managed all my previous builds, so I know a LITTLE about building, but not even close to a professional. I live on the very Southern edge of Zone 7 in Central Minnesota (in fact, Zone 6 boundary is about 2 miles South of me). We have some hot, humid days in the summer, but obviously heating in winter is much more intense.

Asked By Brad VanVickle | Feb 14 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?

Asked By Cindy Bergaus | Feb 27 15
1 Answer

PERSIST in South Florida?

this question is for those familiar with PERSIST style building techniques.
I am considering building a home using PERSIST construction instead of CBS construction in south Florida.
(1) Does anyone know if Grace IWS would effectively stop termites?
(2) would exterior stucco be sufficient in protecting XPS from deterioration and infestation?

Asked By John B | Feb 26 15
1 Answer

What is a correct way of fastening two layers of 2" rigid insulation to the exterior of a 2x6 wall?

I would like to know the correct way to fasten two layers of rigid foam insulation where the total thickness is 4". I am concerned that when hanging this thickness of foam it will be difficult to be sure that the siding application is secure. We will be using HardiePlank horizontal lap siding. This is a form of cement board and heavy on it's own. Any advice.
Thanks

Asked By william dempsey | Feb 26 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

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).

Asked By Dave Brooks | Feb 25 15
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