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3 Answers

How does ambient temperature affect wetting/drying cycles?

Hello GBA pros & community! I've been a lurker around here for awhile, but this is my first post. I'm enclosing a timber-frame in southeastern Manitoba (climate zone 7A), and plan to build a vented roof assembly with dense-packed cellulose insulation. For reference, the specific assembly I have in mind is as follows, from the inside:

-timber rafters
-1x6 T&G pine ceiling
-ice & water shield (interior air-barrier, class I vapour retarder, and temporary rain protection for the timber-frame)
-18" deep non-structural 'trusses' dense-packed with cellulose

Asked By Benjamin Pries | Mar 22 17
15 Answers

Ice dam woes

Gents, I am an Electrical Engineer by profession. Your site is awesome, thanks... it is a shame that the home design and building industry can't incorporate this stuff so that homes are done right the first time around. Sorry... preaching to the choir.

We purchased a 2 year old home that we had inspected prior to purchase. The inspector either was ignorant of the issues in the attic or didn't look at all.

Asked By mg6467 | Mar 14 17
2 Answers

Retrofitting a conditioned attic where there is an attached garage (Phoenix, AZ)

A few years ago, we purchased a 20-year old, single story production home in Phoenix, AZ, where the both air handlers, induced combustion furnaces and ductwork are located in the attic. The ventilated roof is covered with low profile cement tiles and O-Hagin roof vents. We recently had an energy audit where the CFM50 = 2100 and estimated R-23 in the attic the auditor recommended more blown in insulation and upgrading our HVAC and ductwork. But we’d rather create a conditioned attic.

Asked By Eve McFadden | Mar 14 17
5 Answers

Will a Fujitsu RLS3H Ductless Mini Split Heat Pump be enough?

I have been struggling about what type of heating system to put in our home. Ever since I read about the Fujitsu and its 33 Seer efficient system, I have wanted to install 2 in our home, one up and one down. Our home was built originally as a mountain summer cabin with baseboard heating and no duct work. It is in Western North Carolina, elevation 3600 feet.

The first floor is a finished basement made of 8 inch concrete block built on a poured concrete slab foundation that is semi earth-beamed on 2 sides with natural stone veneer on the above ground walls that was quarried locally.

Asked By darejobachjo | Mar 11 17
2 Answers

Hardie Wrap: Over sheathing or foam board?

The question is :Does it matter where the Hardie Wrap is placed? Our builder would prefer to place it over the Avantech.

1. 5/8” sheetrock
2. “smart” vapor retarder (+/-)
3. Roxul R-23 batts
4. Avantech sheathing (taped)
5. 2 1/2” of type X XPS foam (taped). Foamular F250 product is available in 2 1/2 (R=12.5)”.
6. Hardie wrap or equivalent.
7. 3/4" strapping (+/- Coravent SV5 product on top and bottom of walls and windows)
8. Hardie clapboard siding

Asked By Frank Torti | Mar 10 17
1 Answer

Add insulated metal faced panels to the exterior walls of a curling rink arena.

Existing 25 yr old building walls are uninsulated painted concrete block without a vapour barrier. Structure is a pre-Eng steel frame with insulated metal roof.
Building located near Toronto Canada.
Building is maintained close to 40f year round.
Owners have installed new dehumidification equipment and now want to upgrade the walls insulation and seal air infiltration.
The preference would be to use metal faced insulated panels of 5" thickness providing an R of 20.

Asked By user-6788543 | Mar 9 17
6 Answers

New homeowner--question on high cold weather humidity levels and HRV

Good morning,

I'm a new homeowner who just relocated from South Korea to Alaska (military move).

I have a 4 year old house (build in 2012) that's approximately 2600 sq-ft and there are two adults and three children living in the house.

The house has a Lifebreath 200 MAX HRV with what I believe is installed as a partially dedicated system. There are these air inlets in various rooms in the house, such as the bathrooms, kitchen, laundry room, etc.

It has been extremely cold out lately, with highs being between 7-10 degrees F.

Asked By jtludwig | Mar 5 17
1 Answer

Weeping Siding

My family and I purchased a house last year in southern Maine. Over the past couple of weeks, we've had some significant snowfall followed by warmer than usual temperatures. I recently noticed that across the back of the house there are a couple spots where a rust-colored water is weeping out from beneath 5 to 6 courses of wooden clapboard siding close to where the exterior wall meets the roof. I also notice some staining along the soffit vent (photo attached).

Asked By Todd Bridgeo | Feb 24 17
3 Answers

Building a house in Zone 6

Building a house in zone 6. Framing nearly complete. Too cold to roof now with asphalt shingles, but rain protection needed. Roofer asked builder if he should extend the "ice shield" which I understand is vapor impermeable, over the whole roof, or cover with ?

Issue relates to the potential trapping of moisture in the sheathing if two impermeable membranes are used.

Asked By Frank Torti | Feb 21 17
11 Answers

Cracking slab

I had a basement slab poured in May, and it recently cracked in several locations. I am upset that the cracking did not follow control joints. The slab is about 5" thick, and I was aggravated to find that the control joints are only 1/2" deep. From everything I can find, 25% of slab depth is standard. Do I have a leg to stand on in asking the contractor to recut joints to appropriate depth and repair cracks? Slab is 4k psi with rebar on 2' centers poured over poly, 2" XPS, and ~9" crushed stone, in case it is relevant. Thanks for any input.

Asked By Jim Tyler | Feb 20 17
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