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3 Answers

Insulating basement without foam

Can a basement, that is free of bulk moisture problems, be safely and reliably be insulated from the inside without using plastic foam? My thought is: 3" mineral wool (8#/sq ft rigid) against the concrete. Inside the mineral wool, a 2x4 stud wall with exterior face covered by ThermoPly, with seams tapped and corners caulked. The ThermoPly serves as an air and moisture barrier which prevents interior moist air reaching the cold concrete. The stud bays can optionally hold additional bats of mineral wool.

In Energy efficiency and durability | Asked By Jerry Liebler | Sep 29 12
5 Answers

Alphabet soup: ACH, CFM, ELA, MLR, SF

[You'll find a duplicate of this as a comment on an old blog thread
about "how much ventilation", but obviously that's not the way to
get it actually seen and commented on.]

Before my retrofit I did a quick-n-dirty volume and surface area
calculation on my relatively simple Cape, and have just redone it
a bit more accurately. I'm now reading up on blower-door testing
because I expect that eventually the place will get one, and the
confusion over which numbers are which, better, meaningful, BS,
etc is *profoundly* irritating. Anybody who comes along talking

In Energy efficiency and durability | Asked By Hobbit _ | Sep 27 12
3 Answers

Has anyone ever tied a radon vent stack into the plumbing vent stack to avoid extra roof penetrations?

Assuming our new construction waste pipes are all trapped properly there shouldn't be a chance of sub-slab gasses getting into the house. We're on a septic system. We're not really concerned about radon but installed the sub slab perf. pipe as a precaution and currently have the stack capped off in the attic adjacent the plumbing vent stack.

In Mechanicals | Asked By Dan Clere | Sep 28 12
0 Answers

Ceramic tile flooring double layer?

My bathroom ceramic tile flooring just has been tiled and i don"t like it. When I expressed my disappointment my tile layer said, no problem -- I can choose another tile and he will put it on top of the floor he just did. Is this wise to deal with 2 layers?

In Green products and materials | Asked By Jesse Conant | Sep 29 12
3 Answers

Air barrier on floors?

I am currently renovating a 1960's ranch home, adding two additions. The house has been fully gutted. I intend to cover the existing sub-floor ( pine boards on 45 degree angle) with 3/4" Advantek, and screwing the floor in place. The foundation consists of a partial basement and crawl spaces (which I intend to seal and condition). Is there any value to putting down an air barrier before the new sub-floor, and if so, what would be recommended?



In Green building techniques | Asked By Bill Savoie | Sep 25 12
6 Answers

Neat silicone caulk

I have been looking to start making my timber windows internal beaded. i have had a look at some imported windows and have been very impressed at the quality of the silicone applyed to the external face of the window/unit ,no matter how i try i can not get the look i am after .Is there a tool i can use or are the eastern europeans bloody good at tooling of silicone .Any one help .

In GBA Pro help | Asked By graham Cuckson | Sep 18 12
6 Answers

IRC 2009 R807.1 in low infiltration construction

Citing IRC 2009 R807.1 ("Attic Access") [1] my city rejected my 1010 project [2] plan which, in an effort to limit infiltration below 0.6ACH@50P, does not include an access point into the R-91 attic. The slope of the roof is such that, without significant design changes IRC 2009 R807.1 is in effect.

Someone else has been here, I'm sure...got any insights to share?

The idea of including an attic access to comply with R807.1, only to seal it up to meet 0.6ACH@50P is just plain silly; but dropping the pitch of the roof to avoid R807.1 even more difficult.

In Building Code Questions | Asked By Jan Nielsen | Sep 24 12
1 Answer

How to insulate the wood-framed section of a stepped basement?

We will be putting foam on the outer and possibly inner surfaces of our basement but I am wondering how to insulate the above-ground stepped (wood-framed) section of the basement.

In Energy efficiency and durability | Asked By jessie pratt | Sep 26 12
29 Answers

European windows vs. North American windows

I have read many blogs and Q&A pages from this web site and I am still somewhat confused about European windows.

In Energy efficiency and durability | Asked By Steve Young | Sep 5 12
3 Answers

Is 5/8 drywall sufficient to support R-60 cellulose in a ceiling?

Is 5/8 drywall screwed and glued 24" on center sufficient to support R-60 cellulose in an attic ceiling?

In Green building techniques | Asked By Michael Arnold | Sep 26 12
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