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0 Answers

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
0 Answers

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
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
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).

Asked By Jeff Watson | Feb 26 15
24 Answers

Best way to have a wood fireplace?

We are building a custom house, and are nearing our final planning stages before bids with our architect. We are planning to have a wood fireplace on the ground floor, within the building envelope. When it is burning, it will likely to burned with any glass doors on the fireplace open, for aesthetic reasons. It is only going to be used as a heat source as an occasional backup. What are the best ways to minimize the energy problems of an wood fireplace? It'll probably be a zero-clearance type of fireplace. My husband will not agree to a gas or wood stove, so don't even suggest it!

Asked By Clara Kim | Feb 22 15
14 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
4 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
2 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
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.

Asked By Dean McCracken | Feb 25 15
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