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9 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
0 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
0 Answers

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
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
2 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

Asked By Whitney Scurlock | Sep 27 16
59 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
6 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.

Asked By Bernard Lam | Sep 27 16
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