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20 Answers

Choosing a wall assembly: discussion

I really tried to not ask this question since I'm aware that it has been discussed a ton, and I have read a ton on the subject. And even if I've accepted the fact that there's no clear answer, I still have to choose a wall assembly - double wall, 2x6+4"foam, SIP, or some hybrid. Around R40 (I have 12" to work with)

The top priority here is actually budget and ease of construction/quality control.

I've gone through many articles from BSC and GBA amongst many other case studies. This is how my thought process went:

Asked By Bernard Lam | Sep 27 16
0 Answers

Can I install 3/8" T-1-11 clear siding over existing 5/8" T-1-11 siding to create a Board and Batten Look?

My house is currently sheathed in 5/8" T-1-11 siding. I'd like to add another layer of 3/8" clear (no grooves) T-1-11 siding over that and then add 2" battens to create a board and batten siding look. Is this a good idea or a recipe for disaster? I live in Maui on the dry side of the island and get a lot of sun on the south and west sides of my house.

Thanks and Aloha,
Bruce

Asked By Bruce Lowrey | Sep 29 16
0 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.

Asked By John Ranson | Sep 29 16
9 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?

Asked By Eric Teer | Sep 24 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.

Asked By Clay Whitenack | Sep 26 16
1 Answer

Minisplit Design for Whole House

Hello, first of all thank you GBA for all of your articles, I have read many and found them to very helpful and interesting.

I am renovating my house (in Tampa, FL) and installing a new AC system, I will be installing minisplits most likely DIY, but will also talk with installers. I want to see what GBA users recommendations are for how I should design my system.

Asked By Jimmy Black | Sep 29 16
62 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?

Asked By Tony Tibbar | Aug 6 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!

Asked By Kara English | Sep 29 16
41 Answers

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

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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.

Asked By Jake Rabe | Aug 19 16
6 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.

Asked By Clay Whitenack | Sep 22 16
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