insulation boards for under floor heating

[tommyl18]

Hi would I need these if the floor already has insulation under the concrete?

 

[phatboy]

It will save you heating up the concrete as well as the floor surface.....

 

[ericmark]

The problem and beauty of underfloor heating is response time. Having also gone the other way with Myson radiators I know the problems of fast response times when the room would cycle between hot and cold as the radiator cooled down quicker than the thermostat.

With underfloor heating it both takes a long time to warm up and cool down so as long as not switched off the rooms stay at near constant temperature. However the "As long as not switched off" is the real point. Where your not in the house 24/7 then the warm up and cool down times are just too long. As as to selective heating so downstairs warmer in day time and bedrooms only heated at night forget it.

As an extra which can be selected when wanted great but still need radiators for fast warm up times. With large lumps of concrete to heat you will need radiators even more to speed up warm up times.