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5 Answers

Different one-part foams

Hey folks,

I'm installing XPS/EPS rigid foam against my basement walls. I've seen and read on FHB using low-expanding as the adhesive to hold the foam on the walls. I'll be framing a 2x4 wall in front of the rigid foam, so the adhesive only needs a moderate hold.

Great Stuff Window & Door is by far the most common spray foam I see. Its in the big box stores, Amazon, etc. I've put up a few rigid foam sheets in the basement as a test with the Great Stuff and the hold is fine.

In Green products and materials | Asked By Jamie Royal | Mar 26 17
7 Answers

Spay foam on the inside of poured foundation to avoid mold?

I have a question regarding insulating a new construction poured foundation in zone 6B, close to 7A. Twenty miles north of Minneapolis.

Originally I was planning on either a T-Mass or ICF foundation. Both are somewhat more expensive and have a lower R value than what I am now proposing. The current plan is to insulate the outside with 2" foam sheets. This will satisfy code. Then on the inside I would spray 2" of foam and insulate a stud wall with either Rockwool or fiberglass. This wall would be around R-30.

In General questions | Asked By jim sweazey | Mar 26 17
3 Answers

Perlite insulation?

Mineral wool is a popular insulation recommendation, but it seems expensive and has limited supplier options. I came across some info on perlite (and even vermiculite and lightweight expanded clay aggregate [LECA]) as a potential insulation material. I realize that it has a lower R-value per inch than others (perlite loose fill at 2.7/in, vermiculite 2.08/in), but if wall thickness were not a limiting factor, would it be a worthwhile consideration?

In Green products and materials | Asked By Stuart Miller | Mar 27 17
1 Answer

Climate Zone suggestion

Given the importance of climate zone to the nature of this forum I would highly recommend that it be a required drop down field in the "Create Community Question" pages.

In General questions | Asked By Edgar Pankey | Mar 27 17
7 Answers

Second generation Whirlpool heat-pump clothes dryers: Any good?

I would like to install a ventless dryer. The Whirlpool HybridCare duets are the only large ventless dryers on the market. The discontinued WED99HEDW model got a lot of good reviews. The new models don't have many reviews yet, but the reviews they have aren't good.

Here's my question: Is anybody out there actively building the new models into new homes, and are you getting callbacks about their quality? Does anybody have a new model HybridCare, and has it been reliable?

--John

In Green products and materials | Asked By John Ranson | Mar 26 17
1 Answer

Exhaust vent outdoor opening size?

Okay, this is a nitpicking detail, but what does this part of the IRC mean?

R303.6 "Air exhaust and intake openings that terminate outdoors shall be protected with corrosion resistant screens, louvers, or grilles having an opening size of not less than 1/4" and a maximum opening size of 1/2", in any dimension."

Does this mean that the holes in an exhaust vent have to be smaller than an 1/2" circle? That doesn't line up with most of the vents that I've seen on the market, especially dryer vents.

--John

In Building Code Questions | Asked By John Ranson | Mar 27 17
1 Answer

Log-in problem

I signed up for the GBA Prime service this morning. However, when I try to read the restricted articles, the pop-up for registering comes up but does not respond to the "Already Registered? Sign In" prompt.

So I can't sign in. Please help.

Mike Guthrie

In General questions | Asked By Michael Guthrie | Mar 27 17
2 Answers

Still okay to leave Tyvek exposed during construction?

In this older thread, the consensus seems to be that tyvek lasts just fine if left exposed for a few months, based on manufacturer's recommendations and past experience

In General questions | Asked By John Ranson | Mar 26 17
5 Answers

Second guessing ERV/HRV install

Planning for new construction in the Finger lakes region this year. Both our architect (recommends ERV) and a local insulation contractor (recommends HRV) are advising us to install a stand alone ventilation system as we will not have an HVAC/duct work. After reading some of the articles on this site; I'm not sure how necessary it is to take on that expense.

In Energy efficiency and durability | Asked By Nina in CNY | Mar 26 17
3 Answers

HVAC systems

Hi all,

Last week I asked my first question about how to improve my building envelope and reduce mech system costs. using coolcalc.com, I simulated a number of manual J scenarios, I think I have the envelope options down to 1-3 things and will await results from my energy consultant.

The question now remains as to how to best heat & cool my home. On that post, many people suggested Chilltrix, but one poster suggested Implementation risk. They didn't really explain what they meant by that.

In Mechanicals | Asked By Matthew Hicks | Mar 25 17
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