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5 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:

In Green building techniques | Asked By Arnold K | Aug 19 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.


In Mechanicals | 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.

In General questions | 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.

In Green building techniques | 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).

In Energy efficiency and durability | 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)

In General questions | 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.

In GBA Pro help | Asked By Jeremy Kachejian | Jan 12 17
5 Answers

Trying to understand humidity dynamics.

The gym I go to leaves a large box fan on in the locker room 24 hours, presumably so the air movement will dry surfaces (wet floors). I can't imagine they would think it would help with wet clothing left inside the lockers. Accepting that this is inefficient, is it efficacious?

I also know of an archives building that keeps fans on low all the time, with the intent to keep historic articles—especially ones with fabric—from getting mildew. There is a dehumidifier in the room also that keeps humidity below 60%.

In Energy efficiency and durability | Asked By David McNeely | Aug 12 17
2 Answers

Insulation on a 2/12 pitch

Hi all I do love this site it has so much information on it
I am in the planning stages of a new home hope my last stop before I leave earth
I is a mono pitch it will span 32 ft at its widest part I will be using 24in parallel trusses we are in lower michigan north of Detroit.
My thinking is 18in of fiberglass it will leave me with 6 in of air on top and a vent running all the way along the soffit and Ridge
Will this work?
I was thinking if I do need more air in the middle I can put a small step in the roof to grab more like 2 in or so.

In Green building techniques | Asked By Robertsoave | Aug 18 17
6 Answers

Ridge vents: are they susceptible to snow drifts and driving rain?

My current design incorporates ridge vents with simple gable roofs (both house and garage).

It seemed to be both the aesthetic and performance choice. I will be using standing seam steel roofing, which seems to have a very water tight ridge vent design.

In GBA Pro help | Asked By Mai Tai | Aug 17 17
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