Clearly the thermal mass of a floor screed adds to the effective system volume of UFH so it both cycles less and maintains property temperature better then radators with same system volume.
Has this been measured for different UFH systems and different types of screeds?
I have the issue that from our gas usage I can see our heating usage is significantly lower then any reasonable calculation, also it is clear that as we get older we will wish to have higher room temperatures. So am thinking how much a heatpump can be oversized compared to gas usage if we have UFH without giving control/efficiency issues.
I will try to get the UFH heat output as high as is practical as addational pipe and manifold ports cost little compared to overall job.