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17 Answers

Building a Hydronic System Help


In Mechanicals | Asked By Geoffrey Cook | Jun 24 13
6 Answers

Thermal break/insulate between concrete slab and slate

Hi, looking for a way to add some insulation between slate and a slab. I just did a small area about 2' x 5' used some hardiboard to raise it up a bit, but man is it cold! I might tear it up if i can warm it up somehow.
I also will be doing about 100sqft in addition

I have 1" max that I can add to the thickness of the mortar and slate.

any ideas?


In General questions | Asked By mark kessler | Apr 19 13
1 Answer

R values - examples of commercial applications

I am trying to narrow down a list of commercial applications that require the following R-values:


The applications are more for partitioning large areas (loading docks from warehouse, freezers from packaging, refrigerators from packaging, etc). Any chance someone can either provide a range of R-values for different examples of commercial applications?


In Building Code Questions | Asked By Roseann Rimocal | Jun 28 13
1 Answer

The role of the 6-mil poly under the slab, and maybe footings?

The 6 mil poly acts a capillary break between the EPS (pink, blue or white) - if you insulating your slab - and the ground moisture, right? Therefore does the moisture performance of the insulating product matter that much? Going from exterior to interior, its: ground - gravel - poly - insulation - concrete. Assuming yes, the 6mil poly is present, and in that order, any benefits to upping it, to say a 12mil poly to insure less minor tears and better moisture protection? Maybe even an EPDM membrane?

In Energy efficiency and durability | Asked By Sal Lombardo | Jun 28 13
2 Answers

2005 EPAct Tax Credit, Energy Efficient Home Credit

My question concerns new home construction, which allows a contractor or builder a $2,000 tax credit if he or she qualifies. My question is: when it was renewed by congress earlier this year, it was extended to cover "qualified new energy efficient homes sold or leased in 2012 and 2013". What is the definition of "sold"? If it refers to the actual closing, builders will already be running out of time to qualify for this, for it takes several months to complete a new home. If a builder starts a home now, but it's not completed until January of 2014, does he miss out on the tax credit?

In General questions | Asked By Mark Lesperance | Jun 27 13
1 Answer


I'm likely to use the Panaonic ERV bath vent fan(s). Is it permissible to use the vented attic as either the source or destination of this kind of ventilator?

In Building Code Questions | Asked By Jerry Liebler | Jun 28 13
2 Answers

Humid Crawl Space Question in SE

I live in the southeast, so I have the common problem of a humid crawlspace in the summer. I've seen and heard various opinions on what best to do with a crawlspace in this part of the country and have found the articles on this site thoughtful and informative. I recently had an approach suggested to me that I had not heard before, and seems to be a hybrid approach between a vented crawlspace and conditioned crawlspace. The suggestion was to (i) moisture barrier the floor, (ii) seal all of the vents, except for one and (iii) add a dehumidifier.

In General questions | Asked By Brian Jackson | Jun 28 13
4 Answers

Humidity-control switch - always on

We have a bath exhaust fan, controlled by a "Panasonic WhisperControl Humidity Sensing Switch". This switch works great in the heating season, automatically clearing moisture ( Humidity Control Advanced Sensor Technology which detects relative humidity and temperature and will turn on the exhaust fan automatically to keep it in check. The fan automatically turns off when the appropriate combination of humidity and temperature is reached, in all climate zones for all seasons. The WhisperControl Condensation Sensor also has a manual on/off control and a countdown timer. )

In General questions | Asked By curtis betts | Jun 28 13
3 Answers

100+ year old house in Wyoming with hip roof is hot as heck — should we vent it?

Our hip roof is primarily hip with 1 side gable and 1 rear gable. We have no soffit venting and 4 standard square roof vents plus 1 gable vent on the rear west facing gable.

Our house is horribly hot in the summer (we only have a ceiling fan and portable fans in the house an big radiators by all the major windows make an a/c unit troublesome.)

In Energy efficiency and durability | Asked By Natasha Sanderson | Jun 27 13
1 Answer

Options for HVAC for a residential renovation built in 1979 with no A/C

Hello all. New user here.

In Mechanicals | Asked By KENNETH GRAY | Jun 28 13
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