How to Install Electric Mats Beneath Bathroom Floor Coverings

Electric mats can be laid under the ceramic tiles, vinyl tiles, rubber tiles or concrete in the bathroom. They can be laid almost anywhere under the sub-floor, even directly under the shower floor tiles. Electric mats are cheaper to install than hydronic radiant heating, make them an economical choice. However, it is not advisable to tamper with electric wiring if you do not know what you are doing. Before doing any electrical wiring, switch off the power supply.

Materials and Tools

  • Electric floor mats
  • Floor thermostat
  • Chalk line
  • Pencil
  • Blueprints/drawings
  • Tiles
  • Staples
  • Stapler
  • Measuring tape
  • Steel trowel
  • Cement mortar
  • backing board or sheets

Step 1 - Connect the Electrical Wiring

Get an electrician or mat installation professional to install the electrical circuit for the bathroom heat mats according to local code requirements.

Step 2 - Get a Blueprint

Get blueprint or drawing of the bathroom floor that shows the layouts of the heat mats. You can get a custom blueprint from an electrical shop, architect or floor designer. This blueprint should be scaled to represent the actual dimensions of your bathroom floor.

Step 3 - Calculate the number of mats

Using the dimensions from the blueprint, calculate the total area of the floor where the mats are going to be installed. Divide the total area by the area of each mat to get the required number. Trims and cuts will have to be made where the whole mat cannot fit. On the bathroom plan/drawing, you should locate the mats along the walking area. Do not place them under fixtures or cupboards. Allow 6 inches spacing between the mats for bidets and toilets.

Step 4 - Layout the Pattern

With chalk, draw lines on the bathroom floor where the electric mats will go.

Step 5 - Install Mats

Take a stapler and fix the electric mat onto the bathroom floor. Be careful not to damage or scratch the wires inside the mats with staples.

Step 6 - Make Trims and Cuts

For any mats that do not fit as a whole, cut the mats cautiously without cutting or damaging the wires.

Step 7 - Lay the Tiles

Lay some backing board or sheets over the mats. Prepare some cement mortar and spread it over the backing sheets. Gently lay the tiles over the mortar, firmly pressing them down with the back of a steel trowel. Remove excess mortar from the joints and create smooth joints with a steel trowel. Leave the mortar to dry, then clean the tiles with a wet cloth.

Step 9 - Test the Mats

Find the power source (socket) within or closest to the bathroom. Connect an electrical cable from the mats to the power source. Call an electrician to test the electric mats. The electrician will do an Ohm test to determine the flow of electrical current.Ideally, this test should be done prior to covering the electric mats with tiles. If the mats do not work, you may need to remove the tiles and start all over again.