Underfloor heating for your tiles

June 14, 2022 4 min read

Tiles have endless benefits in the decorating realm – they’re sturdy, beautiful, versatile and easy to clean (just to name a few). However, there is one small drawback of fully tiled floors that becomes particularly pertinent in winter. Unfortunately, a tiled floor can feel quite frosty underfoot once the temperature starts to dip. One way to curb this inconvenience is with underfloor heating, a pleasantly toasty solution if you’re not into slippers and socks.

We’re here to talk you through everything you need to know about underfloor heating for your tiles, from the cost to the installation logistics and all that’s in between.

How does underfloor heating work?

The process of underfloor heating is actually quite fascinating and falls into two categories – wet and dry. In dry heating, thin wires are placed on top of the concrete slab and below your tiles. Radiant heat is transferred directly from the wires into the tiles, warming the surface and the room.

Wet heating requires hot water being pumped through pipes in the floor. This method is often powered by water heated by a boiler, but is also amenable to renewables like solar panels and heat pumps.

Thanks to floors being a large surface area, heating them is one of the quickest ways to warm up a room. Stand-alone radiators really can’t compete with that sort of reach! Underfloor heating isn’t just for tiles, either – it can be installed beneath natural stone, timber floors, laminate, cement finishes, and even mirrors and carpet if you fancy.

How much does underfloor heating cost?

There are several factors that will determine how much your underfloor heating will cost. Installation expenses and chosen flooring materials are two key things that need to be addressed. In Australia, the typical cost of laying a heated floor is can be broken down as follows:

• $33 per square metre for an electric in-slab electric underfloor heating system
• $68 per square metre for a hydronic in-slab underfloor heating system
• $105 per square metre for a hydronic in-screed underfloor heating system

Bear in mind that these are just averages – to get an accurate quote, it is best to engage a specific supplier.

After the initial installation fees, there’s another question that tends to pop up – how much does underfloor heating cost to run in Australia? It all depends on the size of your installation area and the temperature you run the system at – plus the difference between operating on off-peak or standard power rates. While hydronic floor heating is more expensive to install upfront, it’s more economical to run – especially on gas or solar power.

According to HiPages, the average running costs of your underfloor heating are as follows:
• Based on a rate of 26 cents per kilowatt hour, a small under-carpet heater can cost up to $24 per month to run (up to 3 square metres)
• Based on a standard tariff of 18 cents per hour, you can expect to outlay in the region of $50 for a small 4 square metre bathroom
• The running cost of a large under-carpet heater is closer to $100 per month (15 square metre to 20 square metre)

Does underfloor heating work with tiles?

Underfloor heating is great for tiled surfaces. Tiles tend to conduct heat well, so the heat is transferred easily to the tiles and warms the room quickly. Tiles also have the benefit of retaining heat, making underfloor heating an energy-efficient option.

What tiles work best with underfloor heating?
When it comes to underfloor heating, not all surfaces are created equal. Your best options are solid surfaces such as stone and ceramic tiles, as they have the least resistance and transfer heat effectively. Even if your tiles are thicker, this will have little effect on the heat output – although it can slightly increase the overall heating time.

Special care must be taken when laying the tiles during an underfloor heating installation. With stone and ceramic tiles, a de-coupling membrane and flexible adhesive are recommended as they reduce the potential for any hairline expansion cracks.

Here are our tips on the different types of stone tiles that people typically gravitate towards, and how they stack up during an underfloor heating installation.

Limestone – Of all stone floor coverings, limestone requires the most care and attention during installation.
Slate – An extremely conductive natural finish, ideal for use with underfloor heating.
Marble – An excellent conductor available in varying thickness, but tends to be quite expensive.
What temperature should underfloor heating be?
This one is a matter of pure personal preference, but most sources recommend setting your underfloor heating to 24°C to start with. Take a few days to adjust the temperature up or down according to your liking. It’s also worth bearing in mind that decreasing the temperature by a couple of degrees might not feel too different underfoot, but it can make quite the positive impact on your power bill.