Underfloor Heating Guides

Underfloor heating explained: electric vs wet systems, installation costs, running costs and compatible floor types.

Underfloor heating comes in two fundamentally different forms, and choosing the right one for your project matters more than any other decision in the process. Electric UFH uses thin resistance cables or mats installed just under the floor finish, wired into a dedicated thermostat. It's relatively cheap and quick to install, at £75-120 per m², and works well retrofitted into a single small room like a bathroom or ensuite. The catch is running cost: electric UFH runs directly off mains electricity, which makes it 3-4 times more expensive to run than a comparable wet system, so it's rarely the right choice for heating a whole house.

Wet UFH circulates warm water through pipes embedded in floor screed or a low-profile dry board system, fed by a gas boiler or a heat pump via a manifold. It costs more to install, £80-150 per m² plus £800-1,500 for the manifold and pump, and takes longer, particularly with a screed system that needs weeks to cure. But running costs are a fraction of electric UFH's, typically 3-5p per kWh on gas or 2-4p per kWh on a heat pump versus the equivalent of 10-15p per kWh for electric. Wet UFH is also considered close to the ideal partner for a heat pump, since both perform best at the same low flow temperatures.

Floor covering matters just as much as the heating system itself. Tile, stone and LVT conduct heat efficiently and are the best-performing finishes over UFH. Engineered wood works well if kept under about 18mm total thickness. Carpet insulates against the heat it's meant to be receiving, cutting efficiency by 30-50%, so it's workable in bedrooms but a poor choice anywhere running cost or heat-up speed matters. Solid wood isn't recommended over UFH at all, since the heat cycling accelerates the gaps and movement that solid boards are already prone to.

Whichever system you're weighing up, the guides below cover installation costs, running costs, floor compatibility and the practical detail of retrofitting UFH into an existing UK home.

A few decisions come up in almost every project regardless of system type. Room size and use matter: a single bathroom rarely justifies the cost and disruption of a wet system with its own manifold and pump, whereas a whole-house new build or major extension makes wet UFH the more economical choice over the system's lifetime. Retrofitting into an existing house tends to favour electric UFH or a low-profile wet dry-board system, since both avoid the floor height increase and weeks of curing time that a traditional screed system needs. And zoning, splitting the system into separately controlled areas, is worth building in from the start wherever possible; it's far cheaper to wire or pipe in separate zones during installation than to add them later.

If you're planning a wider renovation and haven't settled on a floor finish yet, it's worth deciding on the heating system first. Solid wood and thick carpet rule themselves out fairly quickly once UFH is in the plan, which narrows the flooring decision down to tile, LVT, engineered wood or a thin, low-tog carpet, each covered in more detail in the guides linked below.