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2 Answers

Is it possible to insulate an exterior wall masonry chimney with Roxul?

I'm considering buying a small house which has an exterior masonry chimney. Would it be possible to insulate the chimney from the exterior with Roxul to reduce the tremendous thermal bridging through the uninsulated stone? I'm not particularly worried about the aesthetic downsides.

In Green building techniques | Asked By Elliot Firestone | Jun 7 14
1 Answer

Basement slab insulation

I am working on insulating my basement from the interior. I would like to install a 1" layer of EPS as shown in the Fine Homebuilding "The Stay-Dry, No-Mold Finished basement". At this point we are about to pour concrete around the perimeter of the basement where we installed a drain tile, as well as a new 10x10 slab in one corner of the basement. Is there a certain amount of time I need to let the new concrete cure before covering it with the EPS? If I have access to commercial polysio, is that ok for use over a basement slab?

Thanks for any feedback

In Energy efficiency and durability | Asked By Charles Chiampou | Jun 6 14
1 Answer

How to cool my upstairs?

I live in South Louisiana and my house is quite large 5500sqft with the upstairs measuring about 1600sqft. In the summer the upstairs does not get cool. The attic has the insulation that was used when it was built fiberglass pink stuff about 15 yrs old. My attic is also big. Any ideas on how to keep my upstairs cool.? add vents, more insulation, reflective barrier? please help.

In General questions | Asked By Angelique Barrow | Jun 6 14
5 Answers

1.5 story insulation

I live in a 1.5 story cape cod in the Philadelphia suburbs (Zone 4A) built in the 1950s. As expected the second floor has no air sealing and basically no insulation. I am leaning towards using dense pack cellulose to fill the 2x6 rafters as this will not require a total tear down of the drywall. I know without using a vent channel this would require me to use foam on top of the roof deck with at least R-15. I have read all the articles on the site that have to do with my situation but I still have a few questions about this before I get the work started.

In General questions | Asked By Andrew Sirianni | Jun 5 14
1 Answer

Housewraps - Tyvek vs. tar paper

Is there a performance advantage to using Tyvek instead of #30 tar paper when considering house wraps? Thank You.

In Energy efficiency and durability | Asked By Randy Ransom | Jun 5 14
1 Answer

Below grade polyethylene and slab

I am questioning as to the order of polyethylene vapor barrier to foam when placed under a slab. The reason I ask is because I am currently having my house built and today I have discovered that the contractor placed the poly directly on the ground (good drainable material) with the blue board foam boards on top of it. I have read in the past that the poly should be placed on top. I am worried that it has been done incorrectly. Any thoughts to put my mind at ease as I am rather stressed out right now. Thanks in advance.

In GBA Pro help | Asked By Matthew Michaud | Jun 5 14
1 Answer

What's your favorite high-efficiency natural gas fireplace?

We're building a small house with a small heating load. Thinking about a high-efficiency fireplace with electric backup.
What unit(s) do you recommend?

In Energy efficiency and durability | Asked By brian evans | Jun 3 14
3 Answers

Recommendations for exterior trim in the Northeast?

I am replacing windows and want to install a trim that is long lasting and environmentally sustainable.

In Green products and materials | Asked By matt dooley | Jun 1 14
1 Answer

What is the going rate for an energy modeler?

My architect and I are trying to design my home around a Passive House standard. My architect has some knowledge but readily admits to not being very familiar with Passive House design standards. He is well known and has designed many homes in the area, but none to Passive House criteria. Recently, I met with a building science professor who teaches energy efficient building/Passive House and is building his own home to be a non-certified Passive House zero-energy house. He has a Masters in Building Sciences and is a licensed architect.

In General questions | Asked By scott schroeder | Jun 2 14
3 Answers

Living space

Hello,
I'm planning to build a new home on Houston city limit. I would like to build a 2500 sq/ft living space house, but for not be to hard on the budget I would like to live the live unfinished 2 bedroom. In other word take all the mechanical (AC duct, electric) to the room and noting else but just framing.
The builder told me that the city of Houston will not allow that but it also could be that the builder do not want me to save money.
Can you help me with that?

Thanks

In Building Code Questions | Asked By Rocco Locaso | May 30 14
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