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1 Answer

Insulation in a Tight Spot - What to do?

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

How can I fix water running down fascia board causing rot and discoloration?

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

Unheated slab on grade

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

Ensuring the right ventilation approach

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

Insulating cold floor, keeping plumbing serviceable?

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

Blower door disappointment and questions

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

For energy efficiency, when should windows be opened for overnight cooling?

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

Foam board between studs and exterior sheathing?

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

Ice Storage for residential cooling

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
0 Answers

Insulation for a new build in zone 5

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
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