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1 Answer

I'm getting ready to build a home near Indianapolis, Indiana, and I've been referring to the Building Science material for guidance on best practices for construction. When I look through the Building Profile for a Mixed-Humid Climate: Louisville it mentions the use of rigid insulation sheathing. It also notes that in mixed-humid climates (like Indianapolis), roof and wall assemblies are best designed to dry to both the exterior and interior, but the is not always possible when rigid exterior insulating sheathings are used.

In Green building techniques | Asked By Tyson Clemmer | Aug 17 14
8 Answers

I have a question about a situation that a relative has encountered. Zone 5 (SE Michigan), an addition has been added to an old house. The addition has an exposed floor on piers, built with trusses. There is some pink batt insulation near the top of truss cavity, and two inches of foam (XPS) covered by plywood at the bottom. The problem is that the (pex) plumbing which runs from main house and then along bottom of floor has frozen up repeatedly.

In Energy efficiency and durability | Asked By andrew c | Aug 15 14
8 Answers

We had our final blower door test and it wasn't what we had hoped. Our initial cfm50 was 98 with windows and door and all the sheathing done so I expected a substantially better result with insulation and the smart vapor barrier. Our result was 220.

Obviously the higher air leakage has to be from penetrations after the building envelope was finished - vents mostly, I figure.

In Green building techniques | Asked By Lucy Foxworth | Aug 14 14
2 Answers

We have a 2 story home with air conditioning in the Chicago area. In summer, we've done several things to improve our energy efficiency. Our a/c doesn't need to run during the day, even on the hottest days. The interior temp rises gently up to 76-80F and, if needed, the programmed thermostat causes the a/c to run overnight (to 76F) when electricity is cheaper. If we know tomorrow will be 85F+ we set the overnight set point to 74-75F temporarily. It's always cooler at night but the temp varies. On hot days it may be a low of say 75-80F overnight. On warm days the low may be 65-70F.

In Energy efficiency and durability | Asked By w d | Aug 14 14
6 Answers

Someone in my area which is located in a zone 5 recently built a small house and sandwiched used 2.5" polyiso between the studs and the exterior wall sheathing. At first I was skeptical but still intrigued. It certainly simplifies window details compared to foam on the exterior. However I guess you would loose some structural rigidity. But would you really loose that much? If the wall sheathing is screwed on over the foam, the friction of the foam against the studs alone should help keep the wall from racking.

In Green building techniques | Asked By Dillon Vautrin | Aug 14 14
4 Answers

We have a project in a 5a climate zone and another option for cooling that we are considering is an ice storage system (like Ice-Energy/ Ice Bear used to have) for residential cooling. It doesn't seem like this is available at the residential scale. We understand it is a more expensive system but we are interested in the CO2 reduction concept that this could allow. Any thoughts on this would be appreciated.

In Mechanicals | Asked By Nathan Kipnis | Aug 14 14
7 Answers

I am buying a 1900 bungalow in the white mountains of NH, 10 foot ceilings 4 inch walls. The only insulation now is the attic is capped. The heating is hot air, with unsealed or insulated duct work. The house is one story. We are closing in October, so I'll have no access until then. Where should I start?

In Energy efficiency and durability | Asked By Ken Chester | Aug 12 14
7 Answers

I am buying a 1900 bungalow in the white mountains of NH, 10 foot ceilings 4 inch walls. The only insulation now is the attic is capped. The heating is hot air, with unsealed or insulated duct work. The house is one story. We are closing in October, so I'll have no access until then. Where should I start?

In General questions | Asked By Ken Chester | Aug 12 14
Answers

I’m building a brick bungalow in the northern edge of climate zone 5, and I’m trying to decide on insulation for my main floor. My drawing calls for 1” (R6.5) rigid insulation (polyiso) mounted directly on the 2x6 exterior main floor studs, then batts and poly in the bays. Instead of the batts and poly, I would like to do cc spray foam with no interior VB and just drywall with latex paint. Is it okay to spray the inside face of the polyiso? I’m concerned about the heat created when spraying, the vapour permeability for inside drying, and the possible double VB.

In General questions | Asked By Jeff Conners | Aug 15 14
6 Answers

Hi there,

Just want to be sure I'm not missing anything ---from the reading I've done, it seems that most PVA woodworking glues are fairly nontoxic...We have specified no or low-VOC products for our remodel, but our contractor is not an expert in this area. They want to use Titebond II. It seems like a safe choice. Does anyone agree or have a better suggestion for a carpenter's (wood) glue -- aiming to have a minimal impact on indoor air quality--very limited off gassing.

In GBA Pro help | Asked By Mindy Munger | Aug 14 14
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