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10 Answers

Air King Introducing most efficient fan?

I was mulling around on the Energy Star website and came across a listing for an Air King in-line fan. Curious, I checked out their website and also found they have a new line of DC motor exhaust fans coming to market.

According to a page on the 2017 AHR Expo website, these new Air King D4S and D4D fans will be the most efficient exhaust fans on the market:


In Mechanicals | Asked By Lance Peters | Mar 21 17
5 Answers

References for best practices for green building?

What best practices manuals for would people recommend incorporating by reference into a building spec? Rather than reinventing the wheel, where possible I would like to refer to existing documents.

For example, I don't think I can put together something half as good as The Hammer and Hand Best Practices Manual for rainscreen details.


For reference, I'm building a slab-on-grade with double walls and a trussed roof in zone 5 near Rochester, NY.

In Green building techniques | Asked By John Ranson | Mar 21 17
6 Answers

Question about wiring minisplits — electrician's mistake

I consulted with the electrician before he ran the wiring for our new home. I knew that mini splits weren't something they would see everyday, so I wanted to make sure everyone was on the same page. We noted that the unit needed three wires plus the ground, and everyone knew what that meant because I had to run to Lowes to pick up some extra 12/3 wire since they were running low.

In Green products and materials | Asked By Clay Whitenack | Mar 21 17
2 Answers

How do I resolve summertime heat issues and winter ice dam issues in a kneewall attic bedroom w/ a blocked /insulated ridgevent?

Hello, I've really enjoyed your site this winter while researching ice dam fixes and then consequently many other building designs and fixes.

I live in northwest Montana in an old house framed with 2x4's in a smaller house with an attic that's been built out. Our house has a valley on the east and on the west side, we have knee walls upstairs. We are going to get our roof redone this summer with snow and ice shield to the ridgetop.

In General questions | Asked By shmac | Mar 22 17
1 Answer

Spray foam attic with cathedral ceiling

I'm considering spray foaming my attic for energy efficiency and elimination of dust. The attic currently has blown in fiberglass insulation originally installed when the one-story house was built in 1993, which I plan to get vacuumed out prior to spray foaming. Last year I had a metal installed with synthetic underlayment on my A-frame roof. I have seven soffit vents on each side of my home. I also have a cathedral vault ceiling, which limits access in the attic. No ridge vents only a few 18"x 18"square style attic vents placed across the roof for attic ventilation.

In Green building techniques | Asked By uberaustin | Mar 22 17
1 Answer

Finger-jointed poplar: offgassing?

About to trim out an entire house. I have the option of clear poplar and finger jointed poplar. My house is tight, and I have been careful about not ousting mdf for off gassing reasons. The finger jointed poplar is nice because it comes in 16 foot lengths, and it is a little cheaper. I imagine a little greener because it is helping use up scrap wood. My question... Is there any concern of off gassing, similar to mdf?

In General questions | Asked By Dean Sandbo | Mar 22 17
9 Answers

Canned spray foam: a reliable air seal?

Simple question, folks ... Canned spray foam is widely used to seal between a window frame and it's rough opening and around all sorts of envelope penetrations. But are canned spray foams open or closed cell? Does this vary by product? And if they're open cell (my hunch based on stated R values), then are they reliable air barriers if they're less than 3.5 to 5.5 inches thick? See ...


In Green products and materials | Asked By William Costello | Mar 19 17
10 Answers

Whole House Fan with Blown in Cellulose Insulation

I have been working on installing attic baffles in my attic in preparation to blow in cellulose insulation to a height of 18" to achieve ~R60 for the majority of the attic. Per my calculations and manufacturer specs, my attic has 14 square feet of net free exhaust area 50 feet of ridge vent and 18 soffit vents.

In Energy efficiency and durability | Asked By Josh Z | Mar 18 17
10 Answers

Saving a wet crawlspace

Hello All.

I am a long time fan of Fine Home Building, and have been a practicing contractor for the last 5 years here in Halifax, Nova Scotia, Canada.

I have been asked by a client of mine to try and address a moisture issue in the crawl space of their home here in Halifax.

In General questions | Asked By Nick Rudnicki | Mar 19 17
1 Answer

T&G cathedral ceiling air barrier question

We are located in the Finger lakes region of NY and are considering T&G cathedral ceiling. Roof assembly would be Zip Roof Sheathing, un-vented roof with 7" of closed cell foam (R-49). I found a company that uses Lapolla Foam Lok 2000 4G foam with climate-friendly blowing agents. Based on this assembly, I am assuming that I would not need a dry wall layer under the T&G; am I correct?

In Energy efficiency and durability | Asked By Nina Saeli | Mar 20 17
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