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5 Answers

Is a rubber/foam product a good choice for flooring underlayment?

Hi, Is a recycled granulated rubber tire and high density frothed polyurethane foam product on the market the best underlayment for a 2nd story 1883 farmhouse condo with plywood on top of sub floor where I am installing solid oak hardwood (2 1/4" strips)?
I like it because it has much published technical data that I can show my neighbor in the condo below where we are both interested in sound silencing. I thank you kindly for your expert advice.

In Green products and materials | Asked By Mary Schwaba | Jun 26 15
8 Answers

Interior French drain — wall detail

We're installing an interior french drain to address water issues. The grading slopes away from the house and all down spouts are routed 10+ feet away from the house. We have elevated radon and the french drain will be integrated into the existing sub-slab depressurization system. The walls are currently uninsulated, but I plan to insulate the walls with rigid foam in the coming months. The floor will be insulated when the basement is finished in a few years.

In Green building techniques | Asked By Jeffrey S | Aug 17 15
0 Answers

General information on 2"x6" decking

We are in the beginning stages of starting construction on a new home. We have a great room planned with a cathedral ceiling. In the interior there will be exposed heavy timber construction. Above that we would like to see exposed 2"x6" v-matched decking.

In General questions | Asked By william dempsey | Aug 18 15
4 Answers

Does rigid foam sheathing squeak?

I had a Styrofoam cooler in my car this weekend. If it got next to anything else, it made an extremely annoying squeaky noise with every little bump. Does foam sheathing make noise when the house shifts a little from winds or other loads?

In Green products and materials | Asked By Reid Baldwin | Aug 18 15
4 Answers

Will this keep moisture off my fiberglass batts?

Will this 1" XPS board keep moisture off my fiberglass batts in the stud bays in my basement?

In General questions | Asked By Neil Cicciu | Aug 18 15
3 Answers

Closed-cell spray foam application in an unvented detached garage

I have two questions concerning insulating my unvented detached garage. The first applies to the walls. The second to the cathedral ceiling.

Background: I am located in the Midwest at zone 6. I am converting a 420 sq. ft. detached garage into a workshop. I will be installing a GE Zone-line AZ61H15DAB heat pump. The space is unvented and will maintain the cathedral ceiling with no attic space. I hope to keep it conditioned year round as long as the monthly electrical bill isn't astronomical. The floor is concrete. Finished surfaces will be drywall. LED shop lights will complete the space.

In General questions | Asked By Ell Aire | Aug 17 15
5 Answers

Thick masonry walls

I have a friend who owns a 600 yr. old stone house in northern Germany.

In the 70's, interior 2 x 4 walls were added with open cell white foam board 1" thick, no vapour barrier and 1/2 drywall.

They are experiencing mould issues at lower portions of interior walls.

Their intention is to open up the walls and seek advice on possible solutions. One thought is to install dense pack cellulose insulation in 2x4 cavities.

My concern with that is temp change in winter could affect integrity of mortar(stone wall) at some point in its cross section.

In Energy efficiency and durability | Asked By Geoff Bamford | Aug 13 15
1 Answer

Can I use spray foam on a ceiling that also serves as the roof under a deck?

I am replacing an exterior deck over a sunroom.due to leaks in some old EPDM material under a deck.

The sunroom ceiling joists support the flat roof above it, and the deck is suspended above the flat, EPDM covered roof. Can I spray the sunroom ceiling jousts with foam before installing the sunroom headboard ceiling? Would this produce condensation into the sunroom ceiling? The deck above is outside and exposed to summer heat and winter snow.


In General questions | Asked By Terry Hunt | Aug 17 15
3 Answers

Thermal mass loss - flooring over concrete

We are close to starting a pretty good house in zone 4. I've been planning on some high solar heat gain windows in the basement, warming the concrete floor.

But with aging knees and an old dog, I've been wondering if putting a mid-to-dark color sheet linoleum (glue-down) over the concrete would be sensible.

Does anybody know how badly that would affect the heat storage capacity of the concrete?

In Energy efficiency and durability | Asked By Esther Streusand | Aug 17 15
9 Answers

Should I bother with passive solar (Cardinal 180 windows)?

Initially, it seemed like a "no brainer" to go with Cardinal 180 glass on the south side of my home.

I don't have excessive glazing on the south side of my house (240 sqft of glazing on the south for a 3700 sqft house)

Hoever, Joseph Lstiburek has scared me off from this with his statement about overheating (below).

In Energy efficiency and durability | Asked By Derek Smith | Aug 12 15
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