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6 Answers

Here's the scenario:

48' x 104' building in climate zone 5. 48' x 64' of that area will be unheated garage space. I'm still debating the merits of insulating this area. The other park of the building, 40' x 48' will be heated only (no a/c). The area above that is a room in attic area that will be conditioned year round. The room in attic area is 20' x 40', with two 10'x11' spur areas that were allowed by implementing a gable dormer on the main dormer roof line.

My proposed attic ventilation is as follows:

In Energy efficiency and durability | Asked By Rick Van Handel | Aug 11 14
5 Answers

I'm putting recycled 4" XPS under my slab. Zone 6. Do the joints need to be sealed with anything? I'll put poly on top, under the concrete.

In Energy efficiency and durability | Asked By stephen sheehy | Aug 11 14
1 Answer

A few days ago, the friendly folks on this site helped me come up with a basic attic insulation plan for my house. However, there's a potential issue that I could use additional input on.

First, a quick description of the house/project:

- House is in Northern NJ (climate zone 6A)
- Built in the mid-1940s
- Stick construction
- Relatively simple gable roof currently covered with asphalt shingles that will probably need to be replaced in the next five years
- The roof stops at the edge of the house - there are no eaves/soffits, and thus no eave/soffit vents

In Energy efficiency and durability | Asked By Matt Culik | Aug 11 14
1 Answer

I had my roof replaced about 5 years ago. I recently noticed that the shingles overhang most of the roof by 3/4 inch and the water runs directly off.
But in the middle part of the fascia on the back of my home the shingles are flush with the drip edge.
The drip edge lays flat against the top of the fascia, this allows water to actually run down the fascia getting it wet, And some parts are actually rotten.

What can i put there to make the water run off the roof like all the rest of the house?

Here is a link to a youtube video i took of the edge for you.

In General questions | Asked By Tony Bean | Aug 13 14
19 Answers

I'm planning to build a house in Southern Ontario with a slab on grade (actually about 2' above grade) foundation. The slab won't be heated, but will be very well insulated. The house itself will also be very well insulated. There will be a moderate amount of south facing glass with a reasonably high SHGC (around .6).

I'm weighing two different flooring options for the main floor. The first is polished concrete, with the use of some area rugs. The second option is an engineered wood floor, also with the use of some area rugs.

In General questions | Asked By Graham Fisher | Aug 12 14
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
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