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16 Answers

Choosing 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
8 Answers

Custom French trench drain design for specific soil & flooding

I live in rural CO and have a mix of silty fine dirt and clay in my yard. I get some standing water in this portion of my yard during Spring snow melt and flash rains. I also get some of this water (only 1" standing in 1/5 of area) minorly in my 50 year old, 4 foot high crawlspace. It travels under the footer which is about 48 inches deep and 10 feet away on the same side of the home where I have room to put the trench, same side the yard water stands.

Asked By Andy Nels | Sep 28 16
6 Answers

Slab rebar

I am getting conflicting answers on a small house rebar schedule. Some contractors claim rebar is not needed, others say wire mesh if fine, others don't think #4 bar is needed and said #3 is fine, etc.

I called out for #4 rebar at 12" oc

Rebar costs = $4.70 per 20' stick (#4) (21x35 pad)
So on a 3 feet on center pad = 19 sticks or $90
On a 1 foot on center pad = 56 sticks or $263

That's a $173 difference, right?

Asked By Peter L | Sep 28 16
4 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

Is it a good idea to vent a bath fan exhaust out of eyebrow roof?

I originally liked the idea of venting the bath fans out a gable end of the house in order to minimize roof penetrations on the steel roof. I did some research into venting through the main roof soffit vents, and obviously that is not a great idea due to the possibility of drawing moist air back into the roof.

Asked By Adam Peterson | Sep 28 16
39 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
5 Answers

Balancing holes in the ceiling with adequate lighting

Hi all,

Building a new home in central KY, zone 4A. Trying to figure out lighting needs on the 2nd floor and trying to limit the amount of holes in the ceiling. We will not be using canned lights, so that is good, but we are still talking about fixture boxes cutting holes in the drywall. My wife wants to put a few extra lights in the bathroom and bedroom ceilings vs. me trying to get by with just one (in each room) plus (or including) the exhaust fan.

Asked By Clay Whitenack | Sep 28 16
5 Answers

Ideal wall assembly for unconditioned shed

Most GBA discussions focus on conditioned buildings, but I'm curious about the performance of unconditioned structures.

AKA: What's the cheapest way to build a 100-year bike shed? = )

Say we're in climate zone 4c: lots of rain, but only below freezing for a few months.

Since the shed isn't heated, the sheathing will always be cold.
Cold OSB can be trouble (http://www.greenbuildingadvisor.com/blogs/dept/musings/how-risky-cold-os...), so maybe we should go with plywood?

Asked By Kevin Lynagh | Sep 27 16
4 Answers

Insulating rafters in this area

Hi GBA,

I am working on insulating a bedroom and down to a few key areas. I have a set of built in shelves made from 3/4" pine flush with the wall and trimmed in. These are built into the area between a shed dormer and the end of the gable end, making that triangle shape (I think there is a technical term for the area, but I've never found it).

Asked By G S | Sep 27 16
5 Answers

Should I put an A/C return in my encapsulated crawl that has a bit of a smell currently?

I am having a new HVAC pancake system (Trane XR17 and sdv9 furnace) installed in my crawlspace this week. The installers have removed a lot of existing ductwork and I can smell the crawlspace in the house above right now, since the air just flows up. At one point I had considered installing a return in the crawlspace along with the supply registers to help keep the area dry without a dehumidifier that I use right now, and also to take advantage of the "free" cooler air in the crawl in the summer months, but the current smell is putting me off.

Asked By John Sexton | Sep 28 16
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