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0 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
0 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
7 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
3 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I have been looking at your site and find most questions and answers very out of date relating to this subject.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
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
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?

Asked By James Haug | May 25 16
19 Answers

HVAC - Gas vs heat pump vs ducted mini split

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
2 Answers

Condensation in roof rafters in a metal framed house?

Hi, I am trying to build a metal framed house in Bonsall CA, climate zone 10 in California, climate zone 3 nationally. 13 miles inland from the Ocean about 40 miles north of San Diego. One half the roof will be metal trusses, the other half will be conventionally stacked using 2" x 10" metal rafters. On top of rafters is radiant barrier plywood, 40# felt, followed by Spanish Clay Tiles with O'Hagin vents.

Asked By Peter Coz | May 25 16
2 Answers

No minisplit contractors close by

Would it be stupid to install a Fujitsu or Mitsub minisplit with the nearest Fujitsu or Mitsub contractor 60-75 miles away? Can other contractors work on these?

Asked By brad haack | May 25 16
3 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
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