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6 Answers

Radiant Barrier House Wrap- Bug Screen at base of Air Gap?

Per the manufacture specs --- going to have a 1/2 air gap between the wall sheathing wrapped in perforated radiant barrier and the finish wall.

Looking for a durable screen to install at the base of the wall between the finish wall and the sheathing to let the air and moisture escape and no bugs to enter?

It seems Cor-a-vent has a fiber based screen that sounds like it wont last?

Any advice.

In Energy efficiency and durability | Asked By Brent Shafer | Feb 5 16
2 Answers

Advice on yet another vented cathedral ceiling using the "peanut brittle" method.

I am building my home and have a 24'X32' section with 13' walls then a cathedral ceiling at a 7:12 pitch with 2X10's 16OC. The roof is steel with an unvented ridge cap, DuPont synthetic roof underlayment and 19/32 OSB on top of the 2X10 rafters. I will be dropping the ceiling 20" from the bottom of the ridge beam to create a mini attic for several reasons: ease electrical and ceiling fan installs, provide venting into "mini-attice" from each rafter bay into the space and out a gable vent on each end, and ultimately lower my heated space slightly closer to the living area.

In Energy efficiency and durability | Asked By Adam Rahmlow | Feb 5 16
13 Answers

Mitsubisi Heat Pump- heat and cool

I am building a 1 1/2 story barn/garage 36 X 34 with an open upstair 2nd floor. It will have 2" form in the walls and 3" sprayed form in the ceiling. Cement floor. not too many windows and 2 garage doors.

I don't need it heated like a home but just confortable when I work in the barn. I would like to keep it about 40 degrees in the winter when not in use and will rarely need it cool in the summer. I live in southern CT.

I've been looking at the high efficienty units around 24,000 BTU. I also need to be able to set the temperature low (about 40) when not in use.

In General questions | Asked By Fred Gabriele | Jan 31 16
11 Answers

Proper crawl space encapsulation and also radon mitigation questions

Hello, I own a 1968 cape cod style home in East Stroudsburg in the Poconos, PA (region 5). It has a full basement with 7' ceilings and concrete floor with probably little to no crushed stone underneath. At some point, there was a ditch cut out along 2 of the walls, with stone and probably a perforated pipe added, and concrete poured back except for a small channel along the block wall. This leads to a sump pit.

Adjacent to one of these 2 walls is a crawl space entrance where an addition was put in.

In General questions | Asked By Ryan O'Rourke | Jan 26 16
32 Answers

Roxul board used in basement as insulation against concrete wall?

I just watched a mike Holmes episode. He was building out a basement for bar, home theater, gym, etc. against all the walls he used roxul board as an insulation barrier then the walls were framed. I've read where Martin Holliday advised against this practice. Who's right? It makes more sense to use foam or foam board as it won't hold water. Thanks for any clarification on this topic.

In GBA Pro help | Asked By tim gabriel | Mar 5 15
1 Answer

Philadelphia exterior roof insulation with uninsulated brick walls?

In Energy efficiency and durability | Asked By Andrew Austin | Feb 5 16
6 Answers

Excavating near a tree

Apologies if this question is beyond the scope of this forum. I'm trying to figure out how close to a tree I can excavate for a footing, without doing unacceptable damage to the tree. The attached drawing shows the basic situation. The tree is some sort of Asian elm, 40-50 feet tall, with two conjoined (inosculated?) trunks, each about 20" in diameter.

I asked an arborist about it but he was very reluctant to give an opinion. (Makes sense -- he has nothing to gain and a lot to lose by approving any kind of damage.) How do I go about figuring this out?

In General questions | Asked By Ray Sten | Feb 4 16
5 Answers

Roof underlayment

Building in zone 3,cathedral ceeling in 3rd floor bonus room,using 3.5 inches of OCF and 3.5 inches of cheaper in trusses,than using a john mansville nailbase,we will have first layer of 7/16 osb roof sheathing than put nailbase down,what kind of underlayment would you advise to go on top of nailbase and under standing seam room.

Also what is the most cost effective window flashing,zip,tyvek straight flash etc.

In Energy efficiency and durability | Asked By Quinton Bryant | Feb 2 16
4 Answers

Is there any way around putting a heat source in every bedroom?

I was speaking with an HVAC guy in my area today who reminded me that code says we have to have a heat source in every bedroom. We're planning on putting a single head ductless minisplit in our 1450 sf high performance home (to be built next year). Are there other exceptions/solutions out there, or do I just stick a Cadet heater in every bedroom and disconnect them after the inspector checks it off his list?

In Building Code Questions | Asked By Alyssa Hoyt | Feb 4 16
12 Answers

Geothermal Quote question

I am building a new home this Spring and I plan on having ground sourced geothermal. I received a quote from one contractor in my area. His plan is to do a 6 ton horizontal slinky loop field with a 4 ton heatpump. He claims that an oversized slinky loop field performs the best, however I've heard bad things about the slinky loops, and slinky is the only kind of loop they do.

It doesn't seem efficient or cost effective to overbuild the field since that is a major cost. Does anyone have experience with this?

In General questions | Asked By Jordan Garrow | Feb 3 16
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