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4 Answers

Heating Make-up Air

First the details that I hope will answer questions you might have before considering this:

In Mechanicals | Asked By Bill L | Oct 15 13
8 Answers

Heat & cool new PGH house w/ one mini split head & ERV?

We are half way through building a new high performance home in southeastern, CT - 5A. I call it a Pretty Good House +: 2,000sf 2 story, 10" double stud walls with dense pack cellulose, triple pane Intus vinyl windows, simple shape, open 1st floor, high degree of air sealing and paying attention to the details. I have the manual J from our energy rater and I'm trying to finalize the HVAC design as we are ready for mechanical rough-in.

In Mechanicals | Asked By Christopher Vernott | Nov 2 13
2 Answers

Elevated terrace with snowmelt and bluestone 24 x 30 pavers

Has anyone in the cold climate regions installed hydronic snowmelt, with an air gap between the weatherproofing membrane, and the finished materials? I am searching for a product that can act as a mass that fills the void between the epdm, and the bottom of the bluestone. I have hydronic loops within the pitched slab, and then pedestals with bluestone pieces. We need to fill this gap with a product that will heat up as a mass to effectively warm up the bluestone, and then melt the snow. If we don't fill this gap, we don't think this will work.

In GBA Pro help | Asked By victor baiardi | Nov 5 13
2 Answers

Attaching pine board ceiling to airtight drywall

Cathedral ceiling with airtight drywall, want to cover with pine boards. Whats the way to avoid air leakage in the drywall? Is glue strong enough to use on its own? I was thinking of running strips of self sealing membrane along the rafter lines and being careful to only nail at that point. Am I overthinking the process and as long as the nails hit the rafters it won't cause leaks?

In Green building techniques | Asked By darren williams | Nov 4 13
2 Answers

Will blocking off the air conditioner returns and registers in the winter make a difference?

I have a 1992 4,500-square-foot Colonial in NH: It has central air with the handler in the unconditioned attic. Will blocking off the returns and registers in the winter make a difference?

We usually use about 1200-1500 gal of oil which I don't think is too bad. The upstairs bedrooms however seem cool and drafty.

In Energy efficiency and durability | Asked By Henry Pallatroni | Nov 4 13
2 Answers

Foamboard under enclosed concrete porch floor

The back porch of my 1910 rowhouse in Washington DC was hastily converted about 10 years ago into a half bath. There seems to be little or no insulation for the half bath, which is getting quite cold despite being airtight with a newer window. Below the room is an open-air basement entrance way. A 4' x'8 piece of 2" rigid foamboard insulation would fit perfectly onto the bottom of the structure, which is concrete.

In Energy efficiency and durability | Asked By Paul Varnado | Nov 4 13
3 Answers

Thermostat or thermostats for 3 zones of hydronic and forced air

I tried to ask this question at some other places but to my surprise, there was not much response.
Don't think my situation is unique, so hopefully it will help others too.

With the influx of new, smart, wi-fi enabled or networked, large display, etc. thermostats, I would think that there should be a solution to efficiently control 3 zones of hydronic and forced air, together with dehu and circ. Also, I would love to be able to see the reports, track efficiency, usage, etc.

In Mechanicals | Asked By Nick Zees | Oct 31 13
2 Answers

Ideas for air barrier for stepped foundation wall

My house has a couple of unusual conditions:

1. Extra deep footings in south wall because of poor soil conditions. 8' below grade.
2. Using an ICF foundation, but ICF is not made out of foam board, but is composed of blocks like CMU made out of a wood chip/cement mix that is air permeable (Durisol).

I'm worried that air can go from interior through inner wall of the ICF down and around the slab into the soil underneath the slab.

a) Is this an issue?

In Green building techniques | Asked By Jerry Chwang | Nov 4 13
6 Answers

Cellulose insulation & vapor barriers?

Several insulation contractors have recommended loose fill cellulose attic insulation for my 1970's era ranch in northeastern CT. The house is heated with oil via a hydronic baseboard system. Central AC was installed 12 years ago, with equip. located in the attic. There have been no problems with the AC to date. Here is my question:

In General questions | Asked By Marian Heyman | Nov 1 13
2 Answers

Radiant barrier for a temperate climate?

I live in the S.F. Bay area, Oakland to be exact. I am having a new roof put on and am deciding on whether to use radiant barriers or not.

I have read the articles and the comments about radiant barreirs and they are a bit too technical for me. I know the price savings is not worth it, I don't have AC and rarely use heat, although that will likely change as I age. I am most concerned about keeping my house comfortable during heat spells of 78+ degrees which, what with global warming, will likely occur more often.

In Energy efficiency and durability | Asked By db goldstein | Nov 3 13
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