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6 Answers

Insulating I-joists in a garage ceiling

Hello. I have been doing some research to insulate a 2 car attached garage with a room on top. Size is approximately 27x27, new construction. This is in zone-6, Augusta Maine region, and code is R30 for floors.

In General questions | Asked By Tony Bouchard | Nov 25 16
6 Answers

I would like to know how install baffles around the rafters of hip roof portion of the roof.

I'm doing quite a few projects in my attic but have run into some snags and figured I'm reading so many articles on GBA, I might as well ask a question here. I'm breaking my questions into parts below and any assistance is appreciated. Before posting here, I did read quite a few forums on GBA about these topics and on other websites. Thanks for any help you can provide!

1) Insulation Baffles

In Energy efficiency and durability | Asked By Josh Z | Nov 27 16
2 Answers

Methods for keeping cellulose insulation from gas flue line

I am preparing for an attic project: air sealing, and blowing in new insulation.

We have a gas furnace, and its exhaust flows in a Type B vent pipe through the attic and out the roof. The Type B requires 1" clearance to combustibles.

There is already metal around the vent pipe where it enters the attic (picture should be attached). There is some gap between the vent and the metal, which I plan to seal using high temperature caulk.

In Energy efficiency and durability | Asked By Sam Smith | Nov 27 16
7 Answers

Domestic hot water heat recovery: Two systems or one?

We have a large footprint house with multiple bathrooms. The Power-Pipe product seems to be an excellent way of recovering shower waste heat. The question is how to deal with multiple bathrooms that are more than 20 feet apart in a 3 story house. A central drain would be an easy otion and allow the use of one power pipe BUT the hot water woudl need to traverse a great deal of PVC pipe before getting to the power-pipe. It would also be complicated to plu,b to feed from the power pipe to to the mulitple showers drawing from it (in order to plumb the cold side of each).

In Mechanicals | Asked By Edward Cambridge | Nov 25 16
2 Answers

Whether or not to insulate open joist bays between 1st and 2nd floors .

So far Erik North’s Free Energy Maine blog/website has been the only site that actually answers the question about whether or not to insulate open joist bays between 1st and 2nd floors on his blog post “Should I Insulate Between Floors?”. I tried posting a comment on the blog page looking to get his suggestions what is the way best resolve this issue, but it doesn’t go through.

His site led me to the Green Building Advisor webpage, so I am hoping that someone here would be able to provide me with some helpful advice.

In General questions | Asked By susan deissleider | Nov 26 16
9 Answers

Ductless HVAC and humidity control?

We live in Pensacola, Florida and area with extremely high humidity. We are building a new house which is about 2800 sq ft. House consists of a main floor at about 1800 sq ft, second floor at about 800 sq ft and a loft at about 200 sq ft. The current plan is to go with an all ductless Mitsubishi HVAC system, well actually 2 systems. 1 controlling the first floor and a 2nd for the 2nd floor and loft. We have a very competent local installer and I have zero doubts about their capabilities and the pricing I feel is fair.

In General questions | Asked By Thomas Roberts | Nov 27 16
10 Answers

Polyiso foamboard (foil-faced on both sides) used in unconditioned space

Hello All,

I live in Portland,OR climate zone 4 & 5 marine.
I consider it mainly a heating climate and lots of rain.

I have a cape cod style house with 13/12 pitch roof on the main roof.
I have three gable dormers on the front, two new ones and one existing all with 20/12 roof pitch.
I just had ridge vents installed on the main roof and all three gable dormers.

I have managed to keep my new HVAC ducts in the floor joists and the are only exposed in the knee wall area before to going down into the (conditioned) floor/ceiling joists on the way to each room.

In GBA Pro help | Asked By Chalin Hutasangkas | Nov 13 16
11 Answers

Recessed lighting has a bad reputation

Hello! I can tell from reading and from my own experience that Recessed Can Lights are a big frowned upon item for use in Green homes. Mainly the fact that they do not seal very well and are far from 'Air Tight' even if they say so due to a cheap gasket.

I have seen people use foil-faced poly iso and make boxes to place over the recessed can lights. These boxes can be air sealed without having to make contact with the light fixture.

In Energy efficiency and durability | Asked By Nicholas C | Nov 25 16
5 Answers

How to best protect a passive house from wind?

What ideas do you have on how be best protect a house from the Zone IV wind area? I am planning a passive house. Is there specific roof and building outside (like bricks maybe)?

In General questions | Asked By Steve Young | Nov 26 16
2 Answers

Northwest rambler — Attic and crawl space refurbishing

My wife and I are purchasing a 3750 s.f. 1987 rambler in Duvall, WA, climate zone 4/Marine, 17F design temp. The 2015 data indicates 5,000 Heating Deg Days for Duvall. Electricity is $.10/kW. Heating/cooling is currently with a 36,000 BTU packaged unit heat pump supplemented by electric wall heaters.

In Energy efficiency and durability | Asked By Ronald Wilander | Nov 23 16
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