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Frequently Asked Questions


Can I use Thermafloor NZ Undertile Heating system as the sole heat source?

If your room is well insulated and complies with modern insulation levels as set out in the current building regulations, you should be able to use Thermafloor NZ Underfloor Heating as the sole heat source.

What type of flooring can I use over the Thermafloor NZ system?

Thermafloor NZ has a range of specifically designed loose wire and matting heating systems for use under tile, natural stone and under carpet.

Where can I buy the Thermafloor NZ system?

We have many approved distributors, call 0508 432 874 or click here to find a distributor near you.

Do I need specialist skills to install the Thermafloor NZ system?

No specialist skills are required. The Thermafloor NZ system is designed so that any contractor or competent do-it-yourselfer can install it. The kit comes with a comprehensive installation manual, and our instructional videos are available should you need any assistance during installation. A qualified electrician should always undertake the connection of the heater to the thermostat,

How soon after installation can I switch the system on?

For Undertile Heating systems, the heater should not be made fully operational until such time as the tile or concrete installer has confirmed that the cement materials (i.e. adhesive and grout) are fully cured. This may be anything from 1 – 3 weeks. Turning the system on too early could lead to the cement drying out too quickly, creating an unsuitable subfloor.

For Underlaminate Heating systems, once wired and tested, the system may be switched on immediately.

Undertile Heating

How thick is the element?

The undertile heating element, including the full earth braid and double insulation, is between 2.2 to 2.4 mm thick.

Are the heaters water resistant?

Yes, the undertile heaters are 100% water-resistant.

Are the heaters safe?

The Thermafloor NZ undertile elements have been tested and approved by all the appropriate safety testing bodies. Each individual heater is thoroughly tested before it leaves the factory prior to installation and again during commissioning.

To comply with these safety standards, all heaters must be used in conjunction with an RCD. RCD stands for Residual Current Device and is sometimes called an earth leakage breaker or earth leakage detector. RCDs are more sensitive than fuses. They detect any slight loss in current and immediately shut off all power to the circuit before there is a risk of shock.

What sort of floor preparation is required?

As a rule of thumb, if your floor is acceptable for tiling, then it will be acceptable for heating. On particle board or wooden subfloors, we recommend using tile, and slate underlay – hard or sharp particles should be removed and the floors should be completely free from dust, dirt and grease. Waterproofing, if required, is typically done after the heating has been installed but this may vary depending upon the local council requirements and installation details. If in doubt, please contact your local representative.

Can I walk on the installed tile heating before tiling?

The tiler should be the only person to walk on the floor once the heating elements have been installed. If you need to walk on the floor, you should do so only wearing socks or soft shoes.

Does my tiler need any special adhesives?

The floor must be laid with either a flexible adhesive or a flexible additive. Your tiler or tile supplier will be able to advise you on the best type of adhesive for your installation.

How long will it take for the floor to heat up?

This depends on the thickness of the tiles, whether the subfloor is concrete or wood, general levels of insulation and floor insulation. On an insulated wooden subfloor, it takes approximately 20 to 40 minutes for the tiles to feel warm, then approximately 45 to 90 minutes to heat the room. On an uninsulated concrete floor, it will take longer. The floor will also take longer to cool down after the heater has been turned off.

On an insulated wooden subfloor, in a well-insulated room, the floor will be warm in 30 minutes. On an uninsulated concrete floor in a poorly insulated room, it could take up to 5 hours to heat the floor. The longer it takes to heat the floor, the longer the floor will retain the heat.

How much will it cost to operate the heating?

A typical installation will cost approximately 1.5 cents per hour per square meter of heated area when warming up. Once the floor has warmed up, the thermostat switches the heater on and off automatically. In normal winter conditions, if the heater is the only source of heat in a reasonably insulated room, you can expect the heater to be on for between 30% and 50% of the time. This time will obviously vary depending upon the climatic conditions and the comfort levels required. Every 1ºC reduction in the temperature setting of your thermostat will result in a 6% reduction in power usage over 24 hours.

An average bathroom (500 watts) will cost approx $15 to $20 per month using an electronic floor thermostat at normal operating temperature.

***Please be aware that actual costs will vary between electricity supply companies.

Thermostat / Heat Controllers

How can programming save money?

Programming saves money because you do not unnecessarily heat your home when heating isn’t required, i.e. during the day while you’re at work. By lowering the heat during the day, you can realise significant savings: each 1ºC the temperature is lowered during an eight-hour period equals a savings of 2%.

What is the advantage of a pre-programmed thermostat?

Our pre-programmed thermostats come factory-set with a typical energy-saving schedule. For many households, there will be no need to personalise or re-program these factory settings since they are already appropriate for a typical household’s schedule. This means that the thermostat is ready to start saving money as soon as it is installed.

Undercarpet Heating

Are the heaters water resistant?

All Thermafloor NZ undercarpet heaters are 100% water resistant.

How long will it take for the floor to heat up?

The length of time it takes to warm the floor will depend upon the density of the carpet and the subfloor. As with undertile heating, an uninsulated concrete floor will take longer to heat up but will retain the heat for longer. Undercarpet heating will not provide you with an instant source of concentrated heat in the manner of a fireplace or bar heater, rather the whole room is gradually warmed at the same time.