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13 Answers

Adding connected sun room and greenhouse, suggested plans?

I'm thinking of taking this concept and adapting to my situation.

Differences:
Mine can be 15' wide, connected to the house by addition's north wall. Needs to be at least 25' long, up to max 35'.

North wall of addition would join the house, and the long dimension will go south. The sides face east-west.

I plan to add the wall so I can pack it with insulation and make it sturdy for heavy snow years.

In Green building techniques | Asked By Andy Nels | Feb 17 16
19 Answers

Poly vapor barrier under XPS foam board in slab radiant pour

I am building a 28x40 garage in New Hampshire. I am doing an I slab radiant pour. I plan to use 2 inch xps foam board under the slab and as a thermal break to to frost walls. The issue that I have is that this install is for a garage build and will not have a roof over the floor before the slab pour leading to the possibility of rain water ending up being caught between the vapor barrier and foam board before the pour. My question is why would taping the xps foam board seams not act as an effective vapor barrier?

In Energy efficiency and durability | Asked By Jonathan Sinclair | May 26 16
21 Answers

HVAC - Gas furnace vs. heat pump vs. ducted minisplit

It seems the general consensus here, on a very tight or "pretty good" house, is for ductless minisplit. I'm trying to understand the economics.

The following parameters are non-negotiable:
1. Climate zone 3A
2. The house will be piped for natural gas for, at a minimum, cooking and outside grill

In Energy efficiency and durability | Asked By C L | May 22 16
10 Answers

Stamped concrete patio near foundation

Hi all,

I have a couple of questions regarding a patio near the foundation of our house. My wife and I have been dealing with water issues in our basement/crawl space for a while now, and we just recently had a contractor in to seal the vent properly, install a membrane along the foundation wall, and add French drains tied into the downspout.

As the last part of this work, we have removed a surface deck that the old owners installed and are looking to install a stamped concrete patio with the same dimensions (14x30) pitched away from the home. Specifically my questions are:

In GBA Pro help | Asked By Ryan Lambert | Mar 19 16
1 Answer

Paintable low VOC window caulk

Hi,

I am looking for suggestions for a paintable, low VOC interior window caulk for the sealed unit to window stop.

I live in the Vancouver, BC area.

Thanks.

In Green products and materials | Asked By Aaron Gatzke | May 26 16
2 Answers

Exterior insulation behind stone chimney

We are planning to add exterior insulation to an old house. House has 2 layers of siding. There is a large external field stone chimney on the east side and the siding runs up to this. I don't know if this is the same for the inner layer of siding; could be that the siding was installed and then the chimney built. This inner layer has lead paint and may be left in place when adding the exterior insulation (likely spray foam). If removing all siding to access the wall sheathing gives us options for insulating the wall cavity behind the chimney, seems like we should consider this.

In Green building techniques | Asked By TIM LANGE | May 26 16
5 Answers

Foil insulation barriers

I have been looking at your site and find most questions and answers very out of date relating to this subject.
I have just attended a dinner seminar with SMART ENERGY TODAY.
I would like an update on your most recent findings on this subject and any information of the above company.

Thank you.

In Energy efficiency and durability | Asked By Richard Broad | May 25 16
6 Answers

Insulation around basement drain pipe?

We are buying a new house with a basement that we'd like to finish. We are in climate zone 4A, and there are no moisture problems in the basement. The floor cracks in the picture are (reportedly) from 6 years ago when the sump pump failed. We will be installing a backup pump.

In General questions | Asked By Daniel Ems | May 25 16
2 Answers

Cathedral ceiling rafter cavity and insulation

I am trying to figure out how best to use Rock Wool in my cathedral ceiling with the space that I have. I am using 2 x 12 rafters. I am not using spray foam. I was going to build my vent baffle from xps sheets for a 1" air space sub roof sheathing...I was even willing to shrink that space down if needed. I live in zone 3 and would like at least R-35. So with my rafter space I start out with 11 1/2" inches. No matter how I figure it with rock wool batting, I either end up with 2" of dead air space that should be filled with something or 1/4" too much for the space.

In Green building techniques | Asked By Scott Smith | May 26 16
6 Answers

Slab insulation

I need to insulate a slab and usually use rigid foam. However this project is a woody area and there are lots of termites nearby and I know they love foam. Is Roxul drainboard or rock wool a good option in this case?

In Energy efficiency and durability | Asked By James Haug | May 25 16
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