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0 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
4 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
1 Answer

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
1 Answer

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
2 Answers

Looking for ERV install design suggestions

Hi,
I am looking to install an ERV (Renewaire EV90P) to my home and am struggling to find people both interested but also qualified (or interested) to tell me the best install configuration and why instead of just dumping the fresh air into the return plenum. I'm considering now doing it myself and having two return vents (kitchen and bedroom) and two fresh air grilles (living room and hallway). Already have 200 CFM range hood ducted to outside and a bathroom exhaust fan with 60 min. timer to let run extra time up to this point. Blower door test showed 1.9 ACH.

Asked By John E. | Sep 27 16
3 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

Can Tyvek be used over fiberglass insulation that is falling out from between the roof rafters?

My parent's 1975 cape on the Vineyard has an unfinished second floor in which there is one occasionally used bedroom which has been sheet rocked. The rest of the attic is simply exposed fiberglass insulation between the rafters. In some places the insulation is falling out. Can we use Tyvek stapled to the rafters to keep the fiberglass in between the rafters and out of the atmosphere ( exposed fiberglass insulation is an irritant). Technically we want to keep the "attic an unfinished attic".

If Tyvek is not appropriate can we use the pink resin building paper?

Asked By Ruth Cutler | Sep 27 16
5 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
5 Answers

How to encapsulate a brick veneer crawl space?

I am in the process of encapsulating our crawlspace and have a few questions. The house rests on concrete block piers and contains a brick veneer that covers the crawl space and extends below grade. There is a 2-3 inch air gap between the brick and the framing as well as the concrete blocks. The house is located in Climate Zone 3A so plenty of humid air.

Thus far I've installed a 12 mil vapor barrier over the dirt floor and up the sides of the brick wall (leaving a 3 inch gap for termite inspection). I've also closed up and sealed the vents.

Asked By Nate Wofford | Sep 27 16
58 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
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