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13 Answers

Need to correct moisture/mold problem on cathedral roof

Have a room over garage center with closets on both sides between the closet kneewalls and the eaves. Insulation over the room section is 6 inches of foam slabs sealed by "Great Stuff" spray-in foam. Above this ceiling foam and under the roof plywood, there are 1 inch x 20.5 inch unobstructed foam encased ducts between the rafters for venting to the roof peak vent. The side sections outside the knee walls are insulated with rolled fiberglass fiber with durovent ducts above the insulation. There are substantial soffit vents at the bases of the durovent ducts.

In GBA Pro help | Asked By George Baum | Mar 3 16
9 Answers

Mini-splits cause settling & cracking of drywall?

I am pretty committed to the idea of Mini Splits for various reasons I've read about on this site, but our contractor is putting up resistance, saying that we need to have heads in the bathrooms, otherwise temperature differentials will lead to settling and cracking of the drywall, which I have been completely unable to substantiate in online research. Is there any truth to this?

In Mechanicals | Asked By Joseph Yount | Mar 7 16
3 Answers

Blower door test and HVAC ducts

We had our house blower door tested recently. I didn't think about it at the time however we have a geothermal heat pump. The geothermal HVAC unit sits inside the walkout garage and ductwork runs into the conditioned space of the home being tested.

During a blower door test, how significant would the leakage be if any from air being pulled through the cabinet of the geo unit? Do you normally seal of the ductwork at the unit for the blower test?

In Energy efficiency and durability | Asked By Jeremy Kovac | Mar 8 16
7 Answers

Where to put the microwave?

Locating a microwave in a "luxury" kitchen is difficult because a main feature of a "high end luxury" kitchen is that it does not follow convention of putting in an over the range unit-as it would interfere with the aesthetics of the expensive fume hood. Does anyone have any original ideas for locating one that is ergonomically and aesthetically pleasing in the below kitchen that calls for one of those pesky microwave units? I have included a sketch of the kitchen. The yellow area is going to be a glass wall with a door---so that part is out.

In General questions | Asked By Hal Sartelle | Feb 18 16
10 Answers

Pipe out through wall or rim joist?

I need to get a PVC pipe out from the garage. Can I just simply run it through the wall or does it have to go through the rim joist? What would be the benefit?

In General questions | Asked By Joe Blanco | Mar 6 16
1 Answer

Does ASHRAE’s Residential Ventilation Standard 62.2 make sense in a cold climate in a pretty good house?

I'm designing a pretty good home (R33 walls, R60 ceiling, R7 windows and less than 0.6 air changes per hour at 50 Pascals pressure) in Zone 6 and I'm trying to configure a balanced ventilation system. I read several Green Building Advisor articles on mechanical ventilation, including "How Much Fresh Air Does Your Home Need?" which pointed out the potential for moisture issues in warmer climates when designing to ASHRAE’s Residential Ventilation Standard (Standard 62.2), which sets the minimum ventilation rate at 7.5 cfm per occupant plus 3 cfm for every 100 square feet of occupied floor area.

In Mechanicals | Asked By Brad Lystad | Mar 7 16
8 Answers

Add insulation when changing siding?

We are getting our windows done on our 40 year old over the next month (yes they are the original windows LOL). We currently have 2x4 walls with full insulation, zone 6 climate. Has anyone ever increased the insulation R value by adding styrofoam? We are residing the house within the next couple of years.
Thinking about adding 2 inch foam around 3/4 of the house (front wall is brick) just not sure if the cost recovery will be worth it (not to mention the difficulty in matching the wall that meets the brick wall due to the extra 2 inches). It looks like a 48x96 sheet will run $60.

In General questions | Asked By Gary Belcourt | Feb 21 16
4 Answers

Tiny house exterior foam sheathing and insulation question

Hi, I am currently building a tiny house on wheels and have just about finished putting up the cedar lap siding. I just found out I may be in violation of a building code for my tiny house. Due to weight issues my dad and I decided to use insulating foam board sheathing for some of the exterior walls. The front and back as well as the corners were all constructed with plywood sheathing but in between we thought it would be best to use foam board. (We used foam board sheathing in the void spots in the picture below)

In Building Code Questions | Asked By Westin Tromburg | Mar 6 16
5 Answers

Interior vapor barrier for old house?

I have a hundred plus year old building (originally single-family, converted to three-family) on Long Island (Zone 4A) that has a mix of 2x4 framing (balloon & other), with 1" nominal (minimum 3/4", to 7/8") tongue & grove wood sheathing underneath clapboard that's covered with aluminum siding.
We're going to remove the clapboard & aluminum sidings, keep the sheathing and cover it with Tyvek, 1" foam (polyiso or XPS) and vinyl siding.

In GBA Pro help | Asked By Robert Fontanetta | Mar 4 16
1 Answer

Radiant ceiling heat vs gas forced air w/heat pump?

Looking at homes to buy, need to install A/C, wondering about costs & efficency?

In Energy efficiency and durability | Asked By Michele Robarge | Mar 7 16
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