Small wood kiln

[ronstewa]

I am getting ready to convert my utility shed (12x18 7 foot ceiling) to a wood drying kiln. I am pouring concrete for floor. Has any one ever use hot water floor heating to keep concrete warm and help drying? I have it in my shop and love it. 

[doc henderson]

wood for fireplace/woodstove or lumber/boards?  firewood yes.  I have been told, as I had the same question, that the wood on the bottom of the stack for lumber would dry faster as the "radiant" heat would hit it first compared to warm air easily circulating through the stack.  Is it insulated?  do you plan for a dehumidifier also?

[Ianab]

With sufficient airflow (fans) I can't see why it wouldn't work?

You still need to actually get the water out of the kiln once you evaporate it. If you have "cheap" heat (waste wood or solar?) then you can simply vent some of the moist air and the water leaves that way. You have to heat the replacement air, but if the cost is small, that's OK.

A DH system just removes the water, and recovers the heat, circulating that back into the wood to evaporate more water. More complex, but much more energy efficient.  

[K-Guy]

No it is not suitable for lumber drying. Radiant in floor heat is good for maintaining temperature but slow to raise the temperature. Plus the already mention uneven drying in the stack. Electric or hot water coils in the chamber are more efficient.