Choosing which warm water system is suitable is relatively simple.

Firstly it is important to understand the difference between traditional
screed systems and what are known as dry installed systems.
Traditionally underfloor heating involves embedding pipes in screed. Dry installed systems avoid the need for screed but both operate by heat transferring from the water passing through the pipe directly into the floor.

Unlike radiators, underfloor heating systems do not need to run at high temperatures. Heat imparted to the floor is released across a large area
rather than the relatively small and focussed area of a radiator. As such, 
UFH systems do not need to operate at such high temperatures.

Typically, the temperature of the water in an underfloor heating system
pipe is 35 - 55°C (compare this to approximately 80°C flow and surface temperature of a radiator system).

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