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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
2 Answers

Bathroom ceiling and walls

Working on a project in Quebec. It’s an older home and we are remodeling in steps. We rebuilt one wall of the house, leveled and rebuilt a sub floor in this area. This process required us to tear out the bathroom and two closets on each side of the bathroom. This entire section of the house appears to be an add-on at some point in time and the roofline over this section runs at a slightly lower pitch than the main roof. The ceiling in this area is treated as a cathedral type since the rafters hit the top plate at around 6 feet.

In General questions | Asked By Rob Henderson | Aug 16 15
2 Answers

Hi, I am extremely sensitive to chemicals

Hi, I am extremely sensitive to chemicals, and would like to insulate my attic roof.

I am considering cork, but the cost may be prohibitive. Does anyone know of a solution?

The materials have to be non-toxic. If not, does anyone know of an inexpensive solution?

My attic has low beams. So I'd like to put most of the insulation between them, then cover it all with a single layer of insulation. I can't use glue for installation, as I'm sensitive to most glues.

In Green products and materials | Asked By Judith Weiler | Aug 16 15
2 Answers

Water supply to dishwasher

We are just about to install a new dishwasher. During our extensive renovations we have been using Pex for everything. In the installation instructions for the dishwasher they say "use copper piping only". We wonder why this would be. Can we safely use Pex if it is permitted in our area? We haven't checked local regulations but will do so before we progress any further. Thanks.

In Green products and materials | Asked By Susan Berube | Aug 17 15
11 Answers

Economical breathable roof underlayment

So I just got my roll of Solitex Mento in the mail yesterday (for my insulated/vented roof project).

Was at the local big box store getting some staging brackets.....and I find GAF has a BREATHABLE roofing underlayment for about $50 savings when square footage is compared.

The $50 shipping charge for the Solitex could could also be factored in to save $100 for the same square footage.

Hope this helps someone.

In Green products and materials | Asked By Dirk Gently | Aug 12 15
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