What does bathroom underfloor heating cost in South Glamorgan?
Our guide range in South Glamorgan is £650–£2,300 including VAT. Prices in South Glamorgan run at about 7% below the UK guide, based on Wales labour rates.
Electric mat
- Mat under the tiles
Electric, larger room
- Programmable smart thermostat
Wet system
- Screed or low-profile boards
Guide prices for South Glamorgan including VAT. Your itemised written quote after the free survey is the price that counts.
Which towns do we cover in South Glamorgan?
Most of South Glamorgan has moderately hard water. Mid-tone grout and matt tiles hide the odd water mark better than dark grout and high gloss. Hardness varies street by street, so check the figure for your postcode with your water supplier. Whether your Cardiff bathroom is a small en-suite or a large main bathroom, the mat is sized to the open floor, not the whole room.
What the job includes
- Resistance and insulation tests on the mat before, during and after tiling, with the readings recorded
- The electric mat or cable laid to the open floor, kept clear of where the WC, bath and fixed furniture will sit
- For wet systems, pipes in low-profile boards or screed connected to a manifold or single-zone kit, with any boiler work done by a Gas Safe registered engineer
- Insulation boards over the subfloor, so heat goes up into the tiles rather than down into the joists or screed
- A check of the floor construction, the room's heat loss and where the thermostat and supply will go
- A floor sensor set between the heating runs and wired back to the thermostat
Decisions to make first
Thermostat
A simple dial thermostat, a programmable one with set times, or a smart thermostat you can control from your phone.
Floor finish
Tiles and stone pass heat through well. LVT and vinyl can work, but check the maximum floor temperature the flooring maker allows.
Mat or loose cable
Mats are quickest on square, open floors. Loose cable is easier to route around awkward shapes, pipe boxing and a curved shower area.
Insulation board thickness
Thicker boards warm up faster and lose less heat downwards, but raise the floor; the right choice depends on the door threshold and the next room.
Rules that apply in Wales
Electric underfloor heating in a bathroom must be on a circuit with 30 mA RCD protection under BS 7671, and the thermostat is positioned to suit the bathroom zones. There is no separate approval for the heating itself, but it should have its own thermostat and timer so it only runs when needed, and the electrical work must meet BS 7671 — in England and Wales it is notifiable as bathroom electrical work. Any work on a gas boiler for a wet system must be done by a Gas Safe registered engineer.
In Wales, the Welsh Part P also makes a new underfloor heating circuit notifiable, and it covers more bathroom electrical work than the English version. A registered electrician handles the notification.