I purchased a ranch house with natural gas radiant floor heating. It takes about 4 hours to reach my set temperature. Then it overshoots the temperature. Once it gets back down to the set temperature, the concrete (with embedded copper pipes) is cold again, which means another 4 hours to get back up to temperature. Any ideas on how to correct this? Would installing a floor thermostat work? Plus, my boiler temperature is only set at 110 degrees. Should I increase this?

DO NOT INCREASE TEMPERATURE.

You have a control problem and a good floor thermostat will help. Only one problem. It should have been installed when the floor was done.

As HVAC1000 said you have a control problem... DO NOT increase the boiler water temp, you could cause cracks in the concrete. In floor systems should be running to maintain the set temp, and never hooked to a set-back T'stat. You should get a contractor in to evaluate your problem... when you call around, be sure to find one that understands in floor radiant systems. They can be much more complex than a simple boiler system due to the controls and the water mix temps / water controls.