Just curious what some people have been using for HVAC systems with their icf home if any?  pros/cons, reliability?? or can you direct me to a good place to read more about them?
Thanks

I am using slab radiant in this efficient ICF passive solar home. Radiant concrete slabs can require a very low circulating fluid temperature compared to air exchange or conventional radiators.

Low circulating fluid temperatures facilitate the use of highly efficient heat pumps, both geothermal and air source.

Moderate climates, in which Winter lows rarely dip below 0° - 10°F, would indicate the use of a highly efficient air-source heat pump. More severe climates would indicate the use of geothermal.

You also need to provide for air circulation. This is done by using a Heat or Energy Recovery Ventilator (HRV or ERV) and ducting certain areas of the home.

Although I installed radiant heat in the basement floor, I elected to go with forced air for the main level. The same boiler provides the heat source for both, as well as for an indirect domestic hot water heater. The forced air handler has a variable speed blower which constantly circulates the air at low speed so that noise and drafts are unnoticeable. The tight ICF construction with its warm walls makes low volume air circulation practical in achieving a very comfortable environment. The ductwork also allows for a central A/C system, electronic air filtering, whole house dehumidification, and ties into the HRV (heat recovery ventilator) for distributing fresh air throughout the house. I think it's a good lower cost alternative to a full radiant heating system if budget is a strong consideration.

Clark

Posted By Clark on 20 Oct 2011 04:04 PM
Although I installed radiant heat in the basement floor, I elected to go with forced air for the main level. The same boiler provides the heat source for both, as well as for an indirect domestic hot water heater. The forced air handler has a variable speed blower which constantly circulates the air at low speed so that noise and drafts are unnoticeable. The tight ICF construction with its warm walls makes low volume air circulation practical in achieving a very comfortable environment. The ductwork also allows for a central A/C system, electronic air filtering, whole house dehumidification, and ties into the HRV (heat recovery ventilator) for distributing fresh air throughout the house. I think it's a good lower cost alternative to a full radiant heating system if budget is a strong consideration.

Clark

As i'm in the midst of an ICF build, a bungalow, with the same considerations as you have, I was wondering if you use the basement and heat the radiant floor?

John

John, an ICF basement with an insulated floor makes for very comfortable additional living space.  I am in the process of finishing off the basement, but even now, I've turned on the radiant heat and set the thermostat to 70F.  Here's a picture of the PEX tubing as the basement floor was being poured.  I used 2" high density XPS foam covered with 6 mil poly vapor barrier. 

I should have expanded the question a little more, before you had turned onthe radiant floor how warm was the basement, comfort level? How much of the outside basement wall is backfilled?

John

I guess I'm trying to justifiy the cost of installing the PEX and hten not using it, I have 4"s of high density XPS going in before the 4" poured floor. It is a small footprint 1800 sq ft with a walkout.

The basement temperature was a steady 68F when I turned on the heat. The walls are 8" core ICF with 2-1/2" of EPS on each side giving me R22 + whatever 1/2" gypsum board provides. The walls are fully backfilled to a height of 7 feet.

The cost of laying the PEX is relatively small compared to the cost of completing the installation of the radiant heat. I'd do it for sure. At least in part of the floor. You'll be glad you did once it's hooked up and in use. Be sure to use the special PEX that prevents oxygen absorption.

My home is all forced air. I wanted radiant in the basement but time and money kept me from getting it done. If I had to do over again I would have pushed back the basement floor pour a week or two and charged the extra materials....live and learn i guess.

Galnar,

Have you had radiant in-floor heat in the past? If not, why would you have chosen to pay the extra?

I'm wondering since I've never had radiant so I can't miss what I haven't had.

Thanks,
Bruce

Hi tb, I have a Frank Lloyd Wright home built in 1956 with radiant floor hot water heating in 2" iron. It's great. I also installed radiant electric heating in the concrete floor of the bathroom restoration, NuHeat. I recently toured a new home with radiant floor hot water heating that is partially supplied by hot water solar panels. A drain back system. They used plastic tubing with aluminum sheets to attach to the underside of the subfloor and distribute the heat. Hope this helps. Here are my sites for more info: http://www.green-cincinnati.com, http://www.wrightboulter.com/site.

Try balanced ventilation, especially energy recovery ventilation with good filtration (MERV 10 or better). With this method you are exhausting irritants, pollutants and odors being generated in your home, and replacing this ‘bad air’ with better outdoor air (oxygen), and filtering out triggers like pollen and mold spores. In a matter of hours you will be replacing all of the air in your house, and saving energy in the process. Check out this web site - it will get you started. http://www.ultimateair.com

Hey Bruce

I have not had it in the past, but my in laws have it and I just love the way it feels on bare feet on a basement floor.