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4 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

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
5 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
0 Answers

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
0 Answers

I would appreciate a review of an air-source heat pump quote

zone 7 Kenora Ontario, Canada.

I asked for a quote for an ASHP unit that would work for the time being as well as in the near future when the house is expanded...

Some background....

1-short term.. (with the building as is)

-to heat and cool my existing home, 850 sq ft 2x6 framed 20 yr old bungalow on conditioned 5 ft insulated crawlspace...

I completed an online manual J about a year ago and determined as best I could a heat load of about 25000 btu.


Asked By Tim Brown | Aug 19 17
14 Answers

Renovation to address heat gain (summer), heat loss (winter) and ice dams

We have a home at about 6000 feet elevation in Utah. It’s dry, and the temperatures can vary from below zero F in winter to over 100 F in summer. Our house was built in 1994 with some attic space and lots of cathedral ceilings. From what I have observed, the roof/attic was not insulated well when built. This has been partly remedied by blowing in extra insulation into the attic, but most of the cathedral ceilings where framed with 2”x12” with probably 8” or 9” thick batts of fiberglass. In short, the roof has lots of heat gain during the summer and lots of heat loss in winter.

Asked By Chris Butson | Aug 13 17
1 Answer

Rainscreen full of bugs

I've got a building with horizontal cedar siding over 1" furring strips. The vent space at the bottom of the wall is protected by stainless screening to keep the critters out. Unfortunately, it also seems to keep them in. It's ladybugs mostly. It's impossible to keep them out, and they either freeze to death in the winter, or can't escape. If the mesh size had been larger, they could be vacuumed out, although wasps would gain entry and may clog the space with nests.
Pulling the mesh out and replacing it would be difficult, as it is nailed to the wall behind the furring strips.

Asked By Richard Baumgarten | Aug 19 17
6 Answers

Mild climate; expensive cellulose — What to do?

I am getting ready to go to Engineering for a new house in Raleigh, NC.

HDD - 3247 and going down....On border of zone 3 and 4. Technically in 4 but 20 miles from the 3/4 border.

Being in the South, everyone worries about cooling but we usually have 3x the cost in heat (based on last energy audit).

Asked By User-6902085 | Aug 18 17
5 Answers

Ceiling Vapor Barrier

I am in the process of building a 12 inch double stud wall assembly with dense pack cellulose insulation. I am planning on wrapping the inside wall with a smart vapor barrier of either Siga Majrex or Intello Plus. I have heard Siga's Majrex is a superior product in that Intello has had some issues with trapping moisture from fall months when the barrier is mostly open, due to the transition into winter when the perm rate shrinks and the water has not had enough time to transmit out of the wall cavity. (This is advice I received from a retailer of Siga so I am taking it with a grain of salt)

Asked By Chris Roche | Jul 27 17
21 Answers

Insulation retrofit

Looking for some advice on a smallish rehab project I am about to start. I've read many of the great articles and Q&A discussions here, so I think have bit of direction...but as I am novice, I am interested in some feedback before I moved forward.

Asked By Jeremy Kachejian | Jan 12 17
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