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1 Answer

What plumbing system is safe?

Buying house with polybutylene plumbing and read that it can leak. Is it a
health hazard re leaching chemicals into drinking water? Polytheylene (PEX)
tubing can be a health hazard and carcinogenic due to leaching chemicals. Copper has health issues from leaching copper as well.
What is the best plumbing piping that is also safe to our health? Thank you.

Asked By Katherine Webb | Jun 2 14
2 Answers

Spray foam against plywood roof decking questions

I currently have the following roofing system and am located in Northern WV in climate zone 5. Fabral standing seams metal roofing, tar paper and then plywood on 2' center bonus room trusses. I am getting quotes on insulating the underside of the roof decking with spray foam. The HVAC units and ductwork are located in the attic space beside the bonus room. Here are my questions and concerns.

1) I have a vented soffit and vented ridge vent at the moment and should I put up something to keep the air flow before spraying the foam or create a unvented attic space instead with the foam?

Asked By Brian Mallow | Jun 2 14
5 Answers

Back caulking window nailing flanges

Is it common practice to use a specific window flange caulking for back caulking the flange before installation? Does flashing tape and house wrap suffice (assuming that it installed properly) or is caulk important in the case that the tape fails. Or, are you just adding a chance for water that would happen to enter this area to be trapped and rot the framing without knowing? I would like to spare the expense and labor of more caulking if I could but don't want to sacrifice air and water sealing at this crucial junction. Thanks in advance.

Asked By Matthew Michaud | Jun 1 14
42 Answers

Dense Packing Slopes with 11.25 " rafters. Bad idea?

I did a lot of research when I built. Bottom line is that I chose the cheaper easier method and now I'm paying for it. I continue to hear that it's OK to dense pack cellulose in a slope and not vent it or not flash it with closed cell foam. This is incorrect and I can prove it now! Moisture has collected on the back side of the roof sheeting and ice chunks have formed, mostly on the north side of the house. Any where there's snow build up on the south side I have ice formation on the inside of the roof sheathing as well.

Asked By James ODonnell | Mar 4 14
2 Answers

Building in heat/cool/humid region

We are looking to build a new town home in Alexandria VA. According to the Passive House US site we are in the heat/cool/humid region.

Asked By Mike Dyke | May 28 14
12 Answers

Bids on a new construction project

Hi all--I was wondering if you could offer some advice for a dilemma I'm having regarding who will build my house. A few weeks ago, I asked for advice re: HVAC for our new "Pretty Good House." Now, our plans are in engineering and we're getting close to permitting and breaking ground. The company we've been working with is a design-build company--but the two parts are separate. We hired the design part of things and have verbally told the build side of things that we want them to build our house.

Asked By Matt Mesa | May 26 14
1 Answer

An article on the Passivhaus standard for Chinese readers

There is a Chinese translation of the New York Times article on the Passivhaus standard ("The Passive House: Sealed for Freshness") posted on the web: Chinese version of Passivhaus article.

Interestingly, if you perform a back translation of the Chinese (back into English), "pretty good house" becomes "excellence in housing" and "Musings of an Energy Nerd" becomes "crazy energy thinking." That sounds about right.

Asked By Martin Holladay | May 29 14
3 Answers

Cold, wet sheathing on double stud wall?

The exterior sheathing on double stud walls is known gain moisture during winters. The data I've seen is all about "conventional" sheathing choices. There are several brands of fiberglass reinforced gypsum sheathing in the market, being sold as exterior sheathing, all of these products require "bracing" by other means. Denseglass is one brand and it has a moisture permeability of about 20 perms. Does use of fiber glass reinforced gypsum exterior sheathing result in a more resilient assembly than plywood?

Asked By Jerry Liebler | May 27 14
8 Answers

Spray foam inside rim joist?

I know this is quite commonly done but am I creating a durability issue in my unique situation? My rim joist and main floor joist ends sit upon a 2x6 interior basement wall. The outer 2x8 wall of the PWF basement is filled with MW bats and has "Thermoply" on it's inner face and it's top is 1/2 way up the rim joist. (Lateral soil loads on the PWF wall are transferred to the floor system through the rim joist) The "Thermoply" serves as primary air barrier in the basement and keeps warm air from the PT Plywood exterior basement sheathing.

Asked By Jerry Liebler | May 28 14
5 Answers

Tar paper as housewrap

Do you see anything wrong with using tar paper as a housewrap when remodeling?

Asked By don gilbert | May 28 14
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