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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

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
4 Answers

Blown-in cellulose insulation directly against the roof decking?

I have a question about blown-in cellulose insulation for an attic roof. Here in freezing snowy upstate NY, fifteen years ago, we had blown-in cellulose insulation added to the walls of our 103 year old house. Recently a free energy audit, which included IR imaging, showed some settling of the insulation which is to be expected but it also showed several empty areas that the original contractor missed, which was not expected. We now plan to have new insulation blown into the settled and missed areas as well as adding insulation for the attic roof.

In Green building techniques | Asked By Kenneth Patchen | Aug 13 15
2 Answers

Do I need to insulate our slab?

Building a house with a full basement which will have a walk out on one end. Its being built in Johnson City, TN (east TN) -- North Central Region. I have been told that because we are not in an area considered 'cold' or 'extreme' that it is not necessary to insulate the slab with rigid foam. We will be putting a poly vapor barrier under the slab but wanted your opinion on whether we need to also put down a layer of foam.

In Energy efficiency and durability | Asked By Don Welch | Aug 14 15
11 Answers

Positive pressurized attic space for fire protection and summer cooling?

I have a 4 year old Deltec home in Central Washington State. Zone 5B. Deltec homes are essentially round houses that have a center cupola that is vented. (Deltec homes has a web site if you need photos) This house has 2 wings that were stick built on site. The wings have continuous soffit vents and continuous ridge vents. The ceilings between the conditioned space and the attic were meticulously sealed. I am attaching a photo of the cupola from Deltec's web site showing the vents.

In Mechanicals | Asked By Elliott Nelson | Aug 12 15
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