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3 Answers

Will closed-cell insulation prevent bricks (and the mortar) from drying out and eventually falling off of the wall?

My condo association says that closed cell insulation sprayed directly to the back of a brick wall will not allow the brick to dry because there is now airspace, and thus the brick will eventually fall. Is this true?

In General questions | Asked By Ryan Byrd | Jul 7 13
2 Answers

Sound isolation with an unvented attic?

We've insulated the roofline and exterior walls with spray foam insulation and put fiberglass in the interior wall studs, and double drywalled with green glue on bedroom interior walls, but there's still sound transmission between rooms since there's no insulation above the ceilings. Would adding roxul above the bedroom ceilings work? Would that cause any problems? Dust?

In General questions | Asked By andrew shu | Jul 14 13
1 Answer

Is creating positive pressure (post energy work) appropriate?

Good Morning:

In Energy efficiency and durability | Asked By Chip Goyette | Jul 15 13
4 Answers

This has to do with wall insulation in a partial re-build of a 19th cent. House in New Orleans

Climate is Deep South, or hot and very humid in the long Summer. I have heard and read that traditional batt insulation is practically useless. spray insulation is not an option !(for financial reasons) and it may, in any case, be a bad choice environmentally. Celluose . Does this product come in batt form? One further piece of info - the framing is wood on 16" centers. What choices do I have.
Thanks, Michael Higson in New Orleans

In Green products and materials | Asked By michael higson | Jul 12 13
8 Answers

Vinyl Wallpaper

I've been trying to educate myself on vapor barriers since they are by far the most complicated topic I've ever come across.

One thing that kept popping up is the notion that vinyl wallpaper is bad (except for very cold climates). It is a vapor barrier and thus keeps the walls from drying to the inside, right?

Suppose I want vinyl wallpaper in a climate zone 4 or lower. Suppose I like the look of it, and I still want air conditioning. What can I do to make sure it doesn't cause damage to the walls?

Thanks in advance for any help!

In Interior design | Asked By J S | Jul 11 13
3 Answers

Is it time to replace the filter?

I asked this at More Energy Myths a few weeks ago but haven't seen a response so I will post it here.

In Mechanicals | Asked By Bob Rinehuls | Jul 13 13
0 Answers


I found a reference to a composite building product called Newwood, made using a lot of content from recycled plastic bags. Probably similar to several other mixed wood/plastic products out there, but seems to be marketed as a direct substitute for plywood.

Lots of testimonials on its weather resistance, but nothing about structural strength.

Anyone used this stuff in a real-life application?

Something like that might be nice as flooring over a basement slab, come to think of it... no moisture issues, in theory.


In Green products and materials | Asked By Hobbit _ | Jul 13 13
1 Answer

What are the best synthetic slate roofing products?

Must be durable and class A fire rating. Freeze-thaw resistant.

In Green products and materials | Asked By Michael Sanner | Jul 12 13
12 Answers

What product is great for daily use on shower walls that are ceramic tile to reduce soap scum build up and mildew?

Is there a product that is safe to use on ceramic tile on the walls in the shower on a daily basis after taking showers?

In General questions | Asked By Theresa Thompson | May 18 13
8 Answers

Retrofitting loose-fit batts in cathedral ceilings

What is the best method to retrofit loose batts that don't fill rafter cavities? Should we slice pieces of unfaced fiberglass, or blow in loose fiberglass fill? I am concerned that loose fill might plug the ventilation space, and also that the vapor barrier would continue to have substantial gaps.

The kraft-faced 10" batt fiberglass insulation between 2x12 7:12 pitch 24" o.c. rafters is poorly fit, due to variation of the rafter spacing; some of the batts have up to 2" gaps for the entire length. I guess it was deemed good enough in the 80's.

In Energy efficiency and durability | Asked By brian rawlinson | Jul 10 13
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