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2 Answers

How can I seal this space w/ moisture in mind?

Hi All,

I am working on renovating our second floor which includes putting in a master bathroom and gutting and redoing an existing 2nd floor bath. It is a 1952 cape with brick siding on concrete block. The masonry walls are completely uninsulated in most cases. I have taken advice from the GBA site while researching various issues associated with this project and figured this would be a good place to ask about this.

In General questions | Asked By G S | May 2 15
2 Answers

XPS or EPS for venting cathedral ceiling cavity.

I'm planning to create a vent space in a cathedral ceiling slope. Cavity will be 13". I am planning on making a "U" shaped channel out of rigid foam, putting that against bottom of roof deck then dense packing the cavity. It seems to me that EPS is a safer bet here because of its greater permeability over XPS. But XPS is easier to get and stronger. I am a little concerned about dp cellulose crushing 1" of XPS. My understanding is that XPS is rated at 1.1 perm @ 1 inch thick, while EPS is 5.5. Is the XPS still a pretty safe assembly?

In Energy efficiency and durability | Asked By Joseph Carry | May 4 15
7 Answers

Perforated metal used in Roxul rock board install?

Hello,
I've read through this article and tried to contact /find contacts for the owners, but was unlucky. The link to their blog http://agreenhearth.com/ no longer works..

http://www.greenbuildingadvisor.com/blogs/dept/guest-blogs/installing-ro...

In General questions | Asked By Lucyna de Barbaro | Apr 24 15
6 Answers

Skip the plywood, go right ot the Comfortboard IS

I live in central Vermont, heating zone 6, hoping to get a little bit of feedback on the wall system I have in mind for a 4 season workshop (barn), with small efficiency apartment on the second floor.

In Plans Review | Asked By Blake Olson | May 2 15
3 Answers

Thermal break and insulation for gas fireplace flue pipe

We are building a tight and well insulated home in WY. It gets very cold here. We are paying special attention to creating a thermal break and insulating all ductwork to the exterior. They installed a "one pipe" gas fireplace and the metal flue pipe comes straight from the outside with no thermal break. I am told that it must have one inch of air around it so we are not able to insulate the pipe. I had suggested stove pipe insulation which is fire proof but contractor says code does not allow anything.

In Mechanicals | Asked By John Culbertson | May 4 15
5 Answers

Design Temperature

Design Temperature

It seems like most systems are designed around maintaining comfort on the coldest day of year. This can mean that the heating system is specified for 60,000 BTU but your average BTU requirement is 12,000 BTU. The mismatch likely adds quite a bit to the price tag of the boiler or possibly necessitates a boiler instead of something more economical?

Why wouldn’t a secondary heating system that can add heat to cope with the few days of the year where the heat requirements are at their highest be a more economical design?

In PassivHaus | Asked By M G | Apr 29 15
3 Answers

Foam Insulation on attic floor?

I'm about to insulate my attic. I've read a lot about insulating the attic rafters with foam to create an unvented attic. I've read about laying down a think layer of loose fill on the attic floor in a vented attic. I'm having difficulty deciding between them. And now am wondering about a third option.

In Energy efficiency and durability | Asked By Jason Crawford | May 3 15
5 Answers

Need help puzzling through the details of outfitting my house with a mini-split system

Right now my house has a 19 year old 125,000 BTU 80% efficiency gas furnace with ducts in the unconditioned attic, partially buried under insulation. I'd like some help determining if mini-split heat pumps will work as replacements, and in what configuration.

In Mechanicals | Asked By Nate G | May 2 15
13 Answers

Repairing notched bottom plate and floor joist

I am moving a cold air return before I insulate my home and as the title suggests, I'm looking for some advice "repairing" some of the notches.

In General questions | Asked By Nathan Schulte | Apr 29 15
1 Answer

Small spots on inside of Weathershield double pane windows with argon gas

I purchased and installed vinyl clad Weathershield windows. They are showing spots on the inside of the window panes. Has this window failed or is this the result of the argon gas failing. I notice them at the bottom few inches. I am attempting to sell my home and buyers are concerned at what might be going on. They will rely on your opinion.

thank you, Gene.

In General questions | Asked By Gene Schiferl | May 1 15
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