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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
3 Answers

Unvented gas logs

I was so excited to get vent free gas logs last year in my two fireplaces. Now I have a film on all my windows and mirrors. I've read your posts about vent-free products.

My brother is a firefighter and having a FIT that I'm polluting my home. In 6 months I've had 2 serious respiratory infections. (No mystery, right ?)

QUESTIONS: Is there a way to make the vent free logs ... vented? They are in the fireplace already -- I'm not mechanical at all but it seems it's doable. I'd hate to loose the logs but better them than me.

Thanks so much.

In General questions | Asked By Kate Dolan | Nov 27 16
3 Answers

How do I bury a container in a hill (with needed drainage around it)?

I am not planning to have a basement in my new passive house, but I do want a place to store my vegetables and a place to go if there is a tornado. I am considering a shipping container

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

Should I add more venting to my attic, or seal it up, or do nothing?

Should I add more venting to my attic, or should I seal it up and run a dehumidifier to prevent mold, or should I do nothing, or should I go with some fourth option? I read the "All about attic venting" article, but it doesn't leave me certain about how I should proceed.

In General questions | Asked By Michael Bluejay | Nov 26 16
8 Answers

How do I determine the size of a ductless minisplit?

How do I determine the size of a ductless mini-split Heating and Cooling for my new to me Cottage type home built in 1925.

It is 36 feet wide by 26 feet deep. It is an open ceiling type to the roof rafters about 12ft high at the center peak with R-19 insulation, the walls are R-13, Two inside rooms/divider walls with no ceilings (open concept).

The two side outside walks and the front wall get no sun there Is total of 9 double pain windows on these walls the back wall 30ft long has 10 single pain wood frame windows that slide open from right to left.

In General questions | Asked By Mitchell Thompson | Nov 1 16
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