RE: Issues with controlling tempeture in our SIP wall home with Radient hysdronic floors.

We have a concrete slab with a 4 inch mudded tile floor.

We are having two issues:

1. Control: When we set the thermostat  to 70 degrees (Aprox 5' off ground with sensor) even after 24-28 Hours the room = in the 80's yet the floor sensor is only 60 to  62   It's been on for two weeks so should have settled down.

2.Floors are not warm. We are very disappointed that the floors are only slightly warmer than with the hydronic sytem off been long enough to settle in


So- did we waste money putting in a hydronic system in a SIP house?

Suggestions?

I have a SIP home and 2" of concrete for the floors. I have no problems with our radiant heat. We don't use a floor sensor, just a simple wall thermostat. How much insulation below the slab?