Electric vs. Hydronic Underfloor Heating

Underfloor Heating is rapidly becoming one of the most common methods of heating used in Australia. With the heating at the floor level, it is an efficient way to heat any room. There are two main forms of Underfloor Heating, Electric and Hydronic.

What is Hydronic Underfloor Heating?

A Hydronic Underfloor Heating system consists of a network of pipes running under the floor. Hot water heated by a boiler flows through the network of pipes to heat the substrate and therefore heat the room. Typically, in Australia most Hydronic systems are located in the slab not directly below the floor finish.

As a result, it will take approximately two days to heat the entire slab and turn this into a heat bank and generate heat in the room. Once the slab is warm it holds the heat well and becomes an energy efficient heat bank. However, in Australian most areas experience cold mornings and evenings but have it warm during the day, so this is not an effective or useable form of heat as you are unable to reduce or turn off the heat during the day.

What is Electric Underfloor Heating?

An Electric Underfloor Heating system consists of electric heating cables being installed beneath the floor. Electricity then passes along the resistive cables causing them to heat up and radiant the heat into the room. Whilst there are electric systems for in the slab, the majority of electric underfloor heating systems are installed above the slab either directly below the substrate or in a screed.

Advantages and Disadvantages of Electric and Hydronic Underfloor Heating Systems

Both electric and hydronic systems have their own advantages and disadvantages.

  • A hydronic system will typically cost less to run than an equivalent size electric system.
  • An electric system installed directly below the substrate will heat up a lot faster than an In-Slab system meaning the heating does not need to run for as long a period.
  • Electric systems installed directly below the substrate are more suited to the Australia climate than an In-Slab system due to the fast response (heat up and cool down) times and our climate of cool mornings and evenings and warm days.
  • The initial purchase cost of a hydronic system will be significantly higher than an electric system
  • An electric system requires no maintenance. A hydronic system will need regular maintenance of the boiler to ensure the system is maintained.
  • Both electric and hydronic systems can be connected to a solar powered system to help reduce the running costs. In a hydronic application it can also be connected to a gas boiler.
  • If you are running larger areas of electric heating, you may need to add in extra circuitry to operate the system.

Installing the system

The install of an electric system is much simpler than a hydronic system. Typically, the install of an electric system is done by an electrician, tiler, builder or even the home owner themselves. The install process is simple, and the system is then tested by a qualified electrician prior to tiling.

A hydronic system is more complex to install and would require a plumber. Typically, you will need to engage a professional company for installing a hydronic system to ensure the install is carried out correctly to ensure you get an even spread of heat throughout the floor.

Once an underfloor heating system is installed there is little chance of anything going wrong with either a hydronic or electric system. If, however there was an issue an electric system would be easier to locate than a hydronic system.

With an electric underfloor heating system, a technician can put high voltage down the cable to track where the damage is. This can normally be traced down to a single tile that needs to be lifted and the heating cable repaired.  However, with a hydronic system there is simply a leaking pipe causing the water to run along the outside of the pipes making it extremely difficult to pinpoint the exact location of the leak. As a result, it is more likely that a greater proportion of the floor will need to be lifted in order to locate and repair the leak.

Are there any special applications where one system is better than the other?

Whilst both the hydronic and electric system can be used in most applications there are some additional points to consider:

  • In a renovation where there is an existing slab you are not going to be able to add a hydronic system however it will be possible to add an electric system directly below the substrate whilst adding minimal height build up.
  • If you have a large area to be heated and are located in an area where it is cold for longer periods of the year you may find that hydronic heating is a more efficient option for heating an entire home.
  • If you are looking to add heating to only your bathrooms, even in a new build application, the cost of the boiler for the hydronic system would be unreasonable whilst an electric system will be much more affordable.

How do I control my system?

Both Hydronic and Electric Underfloor Heating systems can be controlled by a programable Thermostat. With an In-Slab system you have a lot less control as you will need to allow 1-2 days for the slab to heat up and then the same amount of time to cool down. This means you don’t have the ability to suddenly turn on the heating or turn off the heat with changes in the weather.

An electric underfloor heating system has a lot faster heat up time. It takes approximately an hour for an Undertile system to heat up and cool down so this allows you to set the schedule to have the heating on exactly when you need it and be able to change it to suit sudden outside temperature changes.

Do I need insulation with the underfloor heating system?

Whether you have a hydronic or an electric system it is still recommended to add insulation below the heating to stop downward heat loss as heat moves equally in every direction until it meets a layer of thermal resistance.

By adding a layer of insulation below the heating, you are providing an additional level of thermal resistance which means you are forcing the heat upwards into the room which turns into hot air and rises. Insulation will increase your heat up times and reduce your heat loss resulting in increased efficiency of the underfloor heating system.


Both electric and hydronic systems are going to provide you with the warmth, comfort and luxury that only Underfloor Heating can bring. It can be difficult to know exactly what system is best for your application so if you are still unsure please feel free to reach out to us on 1300 368 631 and one of our consultant’s will be happy to discuss your exact requirement’s.