[Farmall] OT-hydronic radiant floor heat

[Farmallgray at aol.com]

I know a lot of you guys have built shops to work on your tractors so this  
isn't totally off topic. Hopefully this spring I'm going to be pouring concrete 
 in my shop. At the present time, I'm not planning on using the hydronic 
heat,  but I want to put the tubing in for future use.
I'm looking for all the info I can find on insulating the slab and how much  
and what size tubing to use and reinforcing material. I'm not concerned at the 
 moment with a heat source. I just want to get the concrete done. It will  
probably be a few years before I get the walls and ceiling insulated. I have  
been doing web searches and found all the commercial sites on this but the info  
is somewhat vague. I'd even consider a good book on the subject if anyone can 
 recommend one. I would appreciate any good sources of info you guys could  
recommend.
Thanks,
Todd Markle