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8 Answers

Adjusted HRV Calculations

Hi all. I have been looking at options for HRV's for a new, super-insulated home under design. While the Zehnder CA350 would be great, I am pretty sure it may be out of the price range (the exchange rate between US and CAN $ is killing us right now). In my hunt for alternate units using the HVI directory (http://www.hvi.org/proddirectory/CPD_Reports/section_3/index.cfm) for ventilation equipment, I'm finding it challenging because from what I've learned, the HVI uses kind of a bad testing method for equipment, which can often inflate the efficiencies of the units.

In Mechanicals | Asked By Burke Stoller | Mar 12 17
3 Answers

What's the best depth (from the upper surface) for PEX tubing in concrete slab?

Getting ready to do a walkout basement build in far Northern Minnesota. 1140 sq. ft. ICF R-37 walls. I'm going to put put somewhere between 4-6" of foam over crushed surface, vapor barrier, then concrete. Some have posted about a crete-heat type but others have said to raise the PEX into the slab. The concrete guy says he's OK with chairs.

Is there a overall preference out there?

In General questions | Asked By Steve Lenertz | Mar 16 17
22 Answers

Wall moisture monitoring

I'm diagnosing a tricky moisture issue. Part of the process has involved the use of wall cavity humidity and temperature probes. I have some data and I'd like to "peer review" some of the findings in broad strokes.

First off, this great article got me thinking:


In General questions | Asked By Rob Simpson | Mar 6 17
3 Answers

Replacing an external beam with an internal beam

I have a living room that used to be 10 ft wide and 30 ft long, a previous owner enclosed the porch making the living room 20 ft x 30 ft, then added another porch. where the old exterior was was they added an interior 28 ft beam (2x12's) supported with 3 columns, on top of the ceiling rafters is a 2x4 wall to the roof rafters. The house was stick built in 1964

In Interior design | Asked By larrylwill | Mar 16 17
3 Answers

Does anyone in the Phoenix, AZ area install supply registers in the floor of the main floor?

I am specifically talking about a house with a walk-out basement.

I'll be building a new house with a walk-out basement in the low desert. I'd like my supply registers to NOT be in the attic. Seems nobody wants to do that.

Do floor registers really not work efficiently in the low desert?

In Mechanicals | Asked By 447debbie | Mar 15 17
1 Answer

Are Capillary Tubes necessary from 800' to 4000 ' elevation?

Does anyone have any experience shipping Insulated glass units into higher elevations?

New Triple Glazed Argon Gas filled windows are being manufactured in the Northeast and being shipped to the Southwest high desert.The highest elevation the shipper will encounter is 4000-4500' Max.

The weather is very dry most of the year in the high deserts..

In General questions | Asked By Steven Johnson | Mar 12 17
1 Answer

Insulating House in Zone 6A

Hi there, we are currently renovating a 1954 sidesplit in Toronto Canada (Believe this is Zone 6A). On the main floor, there is a 6" slab which doesn't have any insulation or poly below. Likewise, the basement is similar, but only has a 3" slab. We have had to cut channels in the existing concrete slab and will need to pour the new floor for the addition.

We are now looking to insulate both floors. The plans has been to use the following:

In General questions | Asked By James B | Mar 12 17
1 Answer

Install fiberglass batts under foam in cathedral

I am building a new in zone 5. We have cathedral ceilings that were sprayed with 2" of closed cell, followed by 5" of open cell foam(approx R32). The insulation contractor seems to think this will be plenty but I wondered if we could or should add fiberglass batts, pressed up against the open cell foam?

In Energy efficiency and durability | Asked By Michael Brackett | Mar 14 17
7 Answers

Studor vents or vent stack?

I was told by a plumber today that the local code allows for Studor Vents instead of the old tried & true plumbing vent stack. The Net Zero homes they are doing are cutting back on the holes in the roof and the plumbers are using Studor Vents.

On my custom build, should I go Studor or old school vent stack (one 2" stack through the roof)?

Any cons to the Studor?

In Building Code Questions | Asked By Peter L | Mar 14 17
11 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
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