Kestrin Limited - Why Underfloor Heating? UFH V Radiators

BASIC PRINCIPLES

The main difference between the two heating systems is that despite its name the radiator relies on convection for the majority of its output where as UFH provides most of its warmth by radiation creating natural comfort.

To achieve a reasonable room temperature radiators need to be brought up to a very high surface temperature with an appropriately high water temperature supply.

UFH systems have only a small variation between required room temperature and the radiant floor surface temperature, the water supply temperature therefore is considerably lower making heat loss calculations easier to meet.

HOW DO RADIATORS WORK?

We’ve seen before that despite their name, radiators actually provided most of their heat not by radiation, but by convection.

The regular practice of situating radiators underneath windows has come about not simply to counteract cold down draughts but also because of the high heat loss through glazed areas.

Heat energy will always travel from a hot surface to a colder one. In this instance the coldest surface is likely to be the window-the least well insulated surface.

It is a common misconception, even among professionals, that ‘heat rises’. In reality, hot air rises and cold air falls due to differences in air density.

This effect will tend to create a series of stratified temperature layers which in turn creates draughts.

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HOW DOES UFH WORK?

Using the whole floor surface as a radiant heat source provides personal comfort by controlling the radiant heat loss of a body and creates a ‘warm feet and cool head’ sensation.

Due to the small variation between the heated floor surface and the room air temperature unwanted air movement is largely eliminated.

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Why Underfloor Heating? - UFH V RADIATORS

BASIC PRINCIPLES