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63 Answers

Mooney floor

I want to put insulation on top of a concrete floor.
A layer of foam + plywood bolted to the concrete has been suggested. (By Dana I think)
While that looks an good option I've been exploring more low cost options.

What about a Mooney wall, flooring variation.
Thinking about 2x4 + 2x4, filled with blown in cellulose. Likely GreenFiber or InsulMax.

Is that a good alternative?

In Green building techniques | Asked By Tony Tibbar | Aug 6 16
9 Answers

Site-built windows / direct glazing recomendations

Hi,

I'm in the process of building a new construction residential home in climate zone 5 at 6000ft - Boulder, CO. With conditioned floor area at about 3500sqft, I need to install 20 or so fixed picture windows approx 4'x6' on the south side of the house (mainly greatroom/dining room).

Design wind load is 131mph and over all air infiltration rates of <3ACH50 need to be achieved.

The building department does NOT allow 100% vinyl windows - they need to be fiberglass/wood/aluminum/fibrex with U factor <0.30. Site built windows are allowed but this is where it gets complicated.

In General questions | Asked By Bernard Lam | Sep 27 16
10 Answers

Risk of condensation on ducts inside bathroom?

Hi all,

Getting ready to frame the soffit that will hide the ductwork that will run through the bathroom. According to what I read, insulation is not needed on ductwork that is inside the thermal envelope.

Is this true for bathrooms as well? I ask because there is obviously a lot more hot steamy air in a bathroom and I wonder about condensation on the ducts during the cooling season.

In Green building techniques | Asked By Clay Whitenack | Sep 22 16
11 Answers

Polyiso in bonus room

I'm starting the process of finishing my upstairs I'm located in piedmont of north Carolina. My house is 5 years old I have soffit and Ridge vents 1 dormer simple roof line 2x6 rafters . I found a deal on Craigslist for polyiso the problem is its foIL faced on both sides . My plan was to cut and cobble 3.5" pieces between rafters flush to interior of rafters leaving a 2 inch gap from soffit to Ridge vent then install 3 " polyiso on inside of rafters to adress thermal bridging then 1x3 nailers for sheet rock. Is this a sound plan?

In Green building techniques | Asked By Eric Teer | Sep 24 16
2 Answers

Insulation under gravel in slab?

I'm looking at an engineer's drawing (research, not from my own house), and I noted an interesting detail for a frost protected monolithic slab. Working up from the bottom, there's a flat layer of crushed gravel and then a flat layer of EPS. The turn-down footing sits directly on the EPS, and the slab sits on a thick layer of compacted stone over the EPS. The vapor barrier is located in contact with the concrete.

In Green building techniques | Asked By John Ranson | Sep 29 16
4 Answers

Can a ductless mini-split heat pump be installed for a walk-in cooler?

I have a contractor that installed a Fujitsu AOU12RLS3/ASU12RLS3 in a walk-in cooler for a restaurant. They claimed that it was more efficient than a traditional cooling system. Is this an acceptable installation for this system?

In Mechanicals | Asked By Kristin McAlpine | Sep 29 16
6 Answers

Does anyone use the wifi controllers on their mini splits?

Hi all,

I am a bit of a gadget geek (in addition to starting to become an energy nerd). I like dabbling in technology and home automation.

At our old house, I had a nest thermostat controlling a typical 2-stage furnace and a/c unit. I really enjoyed the nest functionality... setting up schedules, tracking usage, turning things off/on while on the road. Also, we lived in an inefficient house, and paid a lot for heating and cooling, so I was always looking for ways to raise/lower temperatures when we were out or sleeping, or any other ways to adjust the usage.

In Green products and materials | Asked By Clay Whitenack | Sep 26 16
5 Answers

Recommendations for a NO VOC durable floor finish?

We are installing white oak hardwoods everywhere in our home. Can anyone recommend the best hardwood sealer/floor finish? We are going to go with the natural color of the wood, but want a NO (not low) VOC product that is also durable. We'd prefer a matte or low sheen finish. Thank you!

In Green products and materials | Asked By Kara English | Sep 29 16
41 Answers

Ice damming — Low-slope roof — Resolvable or hopeless?

[ SUMMARY ]

I own an older home in Ontario Canada that may have been built between the 1920s to 1950s. It originally had knob & tube wiring.

Each winter I have to deal with ice damming along 2 sides of the roof, no where else. The areas in question are a Low-Slope roof (3/12 pitch, east & west side of the ridge) and a Cathedral style roof (8/12 pitch -- inside the home there is a sloping ceiling that is covered by drywall). See a photo of the home: http://imgur.com/sXUzfzG.

In GBA Pro help | Asked By Jake Rabe | Aug 19 16
5 Answers

New Mitsubishi minisplit wall units

Hello,

Does anyone had experience with the mitsubishis mini split MSZ-EF model (comes in 9, 12,15, and 18)? They have a slimmer profile than the prior versions. I am having trouble finding information on the EF (or Zen) series that is geared for the US, and am trying to figure out if BTU and Seer ratings are comparable to the FH range.

Thank you!
-Whitney

In Energy efficiency and durability | Asked By Whitney Scurlock | Sep 27 16
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