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3 Answers

How would homeowners find a truly green contractor?

Where or how would a homeowner be able to find a licensed contractor knowledgeable in the practices and topics discussed on this site, or even green building and healthier building materials in general? Had hoped to be moved in before the holidays and I'm told there is roughly only one month or less of work remaining to be done... but I can't even find a contractor or subcontractors to do it. Maybe I'm searching in all the wrong places? Any advice or help would be immensely appreciated.

Asked By Natasha Reeves | Aug 21 17
4 Answers

Does code allow an exterior stud wall to be cantilevered over rim joist?

New Hampshire, Zone 6a/ 1400 feet Elevation:

I am exploring a way to mitigate the thermal bridging at the rim joist of a double stud wall.

Does building code allow an exterior, load-bearing stud wall to 'hang off' the edge of the rim board? If so, I am hoping this would free up an inch or two to add rigid foam around rim joist and between bottom plate of stud wall and ICF wall. I am thinking either rigid mineral wool or Type II EPS for vapor openness in a cold climate.

Asked By Rick Evans | Aug 20 17
7 Answers

3/12 pitch roof insulation

Hi all.
I sent a question and got a reply on a 2/12 pitch roof.

I have an architect working on my plans now. It is a single-slope roof at the widest part (of 32 or so feet).

I originally was going with 3/12 pitch, but he thought 2/12 would be a lower roof at the tall end, so I said fine!

Now, looking at the problems with 2/12, I asked to go back to the 3/12 pitch. So: If I go 3/12, would I (or should I) use R-60 fiberglass? It will have 24 in. parallel trusses.

Would I still need a cupola? (Zone 6, lower Michigan.)

This is TMI for my small brain...


Asked By Robertsoave | Aug 19 17
3 Answers

Crawlspace with Cellulose Insulation - Go or No Go ?

Greetings GBA folks,

From Columbia SC. Please help determine whether blown in Cellulose between the floor joists is recommended.

Here are the parameters measured in the 20 year old crawlspace:

1. Current moisture content of the joists is at 18 %
2. Relative humidity is at 72%
3. Foundation is drained professionally well down to the footers - no current issue with water, or termites
3. Crawlspace is awaiting contractor to install 20mil vapor barrier to 1400 sqft dirt floor area

Asked By FusionHome | Aug 20 17
6 Answers

Wall Assembly

Below is a wall assembly of one builder we've looked for the purpose of doing the framing, windows/door installation and the various barriers (WRB, Vapor and Air). I wanted to know everyone's thought are for my climate in Ottawa, Canada.

My opinion is I don't think this is a good wall assembly for the following reason:

Asked By Arnold K | Aug 19 17
1 Answer

Flat roof membrane types

Hi All,

I'm looking for advice on the best type of flat roof membrane. I'm currently getting estimates to have a new one put on, with estimates for TPO, EPDM, and fibertite. The roof has ponding issues so I'm also going to have that corrected with tapered foam insulation. I live in zone 6A. Thanks for your insights!

Asked By Tina D | Aug 20 17
13 Answers

High humidity in between floor space in 2-story home in Zone 3A

Our home has a "crawl" space in between the first floor and second floor, all of our AC duct which is insulated is in this area. It appear to be well insulated, and is the same temperature as the house most of this time, within 1 degree or 2.

The issue is the humidity in this area is 30% higher than inside the house most of the time. The humidity in the house can be as high 58% in this humid season right now, but in the crawl space it is as high 89-90%. It seems like it should not be this different?

Asked By Momndad | Aug 18 17
2 Answers

Remodel with raised floor: insulation options?

we recently began a renovation and I am hoping to get some guidance on best practices for insulating under our floor. We added a new attached garage and are renovating the old attached garage into interior space. The old garage was two steps down from our home and we will be adding I joists across the area to bring the renovated space onto the same level as the rest of the house. We live in climate zone 6 and the old garage floor is 4" concrete with good drainage but no poly under.

Asked By Brian Lueking | Aug 20 17
2 Answers

Why does GBA promote PHIUS as opposed to the Passivhaus Institut?

You say the PassivHaus Institute is in Germany. No such organization exists. The least you could do is accurately spell the name of the organization you reference. The Passivhaus Institut who coined the term "Passivhaus" and established the global "passive house" standard in or around 1990 exists in Germany. You then draw a direct comparison by falsely stating that "we have a branch here in North America called..."PHIUS." Who is "we?" What authority associated with the Passivhaus Institut gives you authority to claim that you have a branch here in North America????

Asked By Michael R Conners | Aug 20 17
5 Answers

Average quality built homes needing makeup air because they are airtight

I have a question in regards to homes being built (not necessarily green homes) that are subject to the new energy code with air sealing and blower door tests. These homes are being built with average, code minimum building materials and after a blower door test it is showing the house is tight enough to require make up air.

Seeing as these are not green homes, there was no plan in place ahead of time for a system to bring fresh air into the house. Are you seeing this as a problem in other states as well?

Asked By Brian Ducharme | Aug 17 17
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