Heat Sources

At Optimum we get asked about Heat Sources all the time and like everything in life there are advantages and disadvantages with every option.

What is important is that what ever heat source you choose to supply your underfloor heating, it is designed and integrated correctly. Heat Sources generally fall into two categories:

  • Conventional high temperature boilers fuelled by gas, oil or electricity.
  • Heat pumps, ground or air source types.

Conventional heat sources are relatively cheap to install but running costs are governed by the current cost of gas, oil or electricity.

Heat pumps require a larger initial capital outlay and are also governed by the cost of electricity but are far more efficient with a coefficient of performance (COP) of between 3 and 5. This means for every 1 kilowatt of energy you put into them you will get between 3 and 5 kilowatts of useful heat energy back out of them.

The decision ultimately is governed by the customer's budget and whether they have the long or short term outlook with regards their initial investment.

The important consideration with regards the underfloor heating is if it is going to be supplied by a heat pump, Optimum changes the design parameters to suit this type of heat source. What this means is more pipe is specified to go into the floor structure so the system can run at a lower flow temperature whilst providing the same comfort levels in the building.


Heat pumps are gaining popularity because of their green credentials and a lot of our clients are opting for this type of heat source.

IMPORTANT- Always choose your heat pump supplier carefully, many companies have impressive marketing departments but do not deliver a good overall service. Optimum deals with many suppliers and installers and can recommend how to achieve the best overall system.

Another popular and sensible option is to "future proof" your underfloor heating system. What this entails is installing the underfloor heating pipe work to suit a heat pump even if initially you are supplying it from a conventional boiler. This then gives the client the option, at a later date, to change their heat source to a heat pump.

The extra cost of future proofing your underfloor heating system is small and should definitely be considered as it is impossible to alter the pipe work once it has been installed.