Re: [GBlist] Radiant floor question

[Sarah Holland/David Foley <hollandfoley@acadia.net>]

Title: Re: [GBlist] Radiant floor question

on 3/27/01 3:51 PM, Gavin Bowie at gbowie@GGA.com wrote:

> A perhaps naive question: 
>
> Can one (and more importantly, would it be possible, desirable, and prudent to)run chilled water through a radiant flooring system to provide cooling in the summertime in a northeastern US location? (Residential project ~2700 sf)
>
> It seems a waste to install a radiant floor heating system and have to install A/C ducts as well. If good natural ventilation and appropriate shading is provided, why not use the thermal inertia of the ground-source heat pump directly rather than running a chiller to cool the air?
>
> I realize that dehumidification is most of the cooling battle and that this would not provide any dehumidification. 
>
> Would there be problems with condensation? Any other reasons not to have a chilly floor besides having to wear slippers? I am quite sure I have not thought of all the ramifications.
>
> Thanks for your always constructive advice... 
>
> Gavin W. Bowie 
Dear Gavin,

I have heard from good mechanical engineers that in the Northeastern US, this strategy would often lead to condensation on the slab.  I have not personally seen a written study on this, but the anecdotal evidence I’ve heard matches my common sense.  But in this region, humidity is often a greater problem than actual air temperature.  A smaller AC system, just for dehumidification, could perhaps be combined with a cooled slab, so that the air in the vicinity of the slab would be dry enough not to reach the dew point.

Best wishes,

David Foley
-- 
Holland & Foley Building Design L.L.C.
232 Beech Hill Rd.
Northport, Maine 04849 USA
p: (207) 338-9869 f: (207) 338-9859 e: hollandfoley@acadia.net