insulating a floor with pex in floor heat

larryyost

i just bought a house that is two years old, it is 70 feet long and 28 feet wide. there are BCI floor joist 16 inches on center. in each joist bay there are two 1/2 inch pex pipes that are nailed to the bottom of the sub floor. the flooring in the house is mixed between laminate carpet and tile. there is insulation in each bay R21 and it's flush with the bottom of the joist. my question is should i push the insulation up to the top of the joist to help keep the pipes and the floor warmer or should i leave it the way it is because it keeps the joist warm and dry. there isn't a moister problem under the house. is there something else is should do? it seams like the floor are never consistently warm and it seems like the boiler is running more than it should  the water stays around a hundred and seventy any help would be helpful thanks 

Paul Pollets

Plates

Aluminum transfer plates will help the performance significantly.  Plates increase BTu transfer by 30-40%  and reduce boiler water temps.  The "near-boiler" piping may have to be modified to install a motorized mixing valve, to give a dedicated setpoint temperature for the zone and eliminate any ticking sounds.