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0 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.

Asked By TIM LANGE | May 26 16
19 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

Asked By C L | May 22 16
4 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?

Asked By Jonathan Sinclair | 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I have been looking at your site and find most questions and answers very out of date relating to this subject.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.

Asked By Richard Broad | May 25 16
3 Answers

PEX A vs. PEX B

I am obsessing over which pex to use for a whole house manifold installation. The choices are pex-a (uponor) vs pex b (viega).

Uponor seems easier to work with, less kinking, better flow etc.

What I am most concerned with is:

1.longevity (this is my forever house)
2. safety (leaching of chemicals into drinking water)

I am on a well.

Any input as to the longevity and safety of these two different types of pipes?

Dean

Asked By Dean Sandbo | May 26 16
11 Answers

Attic insulation quandary

Seeking advice on renovation plans for a 1910 house in ND - Zone 7.

HOUSE DETAILS:
- 2 1/2 stories above ground with full basement.
- 2nd story has 'sun porch' facing south.
- 2 layers of siding. Inner layer has lead paint (of course)
- Insulated in the 70's with formaldehyde foam, holes drilled through exterior to fill cavities.
- High efficiency propane furnace, forced air.
- 2 chimneys.
- 1st in middle of house used for original oil-burner furnace and water heater. Now used by wood fireplace in basement.

Asked By Tim Lange | May 16 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.

Asked By Daniel Ems | May 25 16
9 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:

Asked By Ryan Lambert | Mar 19 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.

Asked By Scott Smith | May 26 16
17 Answers

Direct vent vs power vent gas water heaters

A recent blower door test/audit has alerted me to the fact that my natural draft hot water heater can backdraft in worse case scenarios (range hood/clothes dryer/bath fan on). It seems to reverse back to a correct draft after a few minutes. It's only about 6 yrs old, so I hate to replace it, but not as much as I hate the idea of the back draft.

Asked By Erik Addy | Mar 8 16
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