In recent years, there’s been an explosion in the popularity of underfloor heating – particularly in new-build homes. Most people understand the basic premise of the technology and the idea that heating from below can vastly improve efficiency, but just how does underfloor heating work?

How does underfloor heating work

The main difference between underfloor heating and traditional systems

Traditional radiators and wall-mounted heating systems work on the premise of radiation and convection, sucking air from the floor and heating the area immediately above and around the radiator. As hot air rises, traditional heaters cause a mass of warm air to build at ceiling level, leaving the floor the coldest area in a room. Eventually, this warm air cools and drops to floor level again, ready to be sucked back into the radiator and creating a circular airflow.

Conversely, underfloor heating generates a more even distribution of heat, rising across the entire area of a room rather than just the immediate area around the heater. As the heat produced is used more effectively, underfloor heating can operate at far lower temperatures (in some cases, as much 66% lower), offering considerable cost savings.

Heating from below is substantially more effective and efficient

Underfloor heating is essentially akin to placing a large radiator under the floor. A network of water-pipes or electrical cabling is fitted directly under the floor, meaning the heat generated can be distributed more effectively and efficiently around the surface area and, in turn, space above.

The two main types of underfloor heating

There are two primary methods of fitting underfloor heating to a home, each with their own particular advantages:

Electric underfloor heating: In an electric system, an ultra-thin wire is placed directly under the floor, commonly on a matt or foil. When the system is activated (typically from a thermostat control), power passes through the wire, causing it to generate heat. As electric systems are remarkably thin, they are particularly suitable for renovation projects, where raising the floor level might cause problems. Most competent DIY’ers can lay electric underfloor heating quite easily, and sites like offer everything you need – from wire kits to mats and thermostats.

Water-powered underfloor heating: Water-powered heating systems work more like traditional radiators, just with the heated water passing through a circuit of pipes placed under the floor. These pipes are installed in a shape designed to provide the evenest heat distribution. Again, the water temperature is controlled by a thermostat and can be allocated on a per-room basis. Any source can be used to heat the water – biomass, standard, combination, stoves, heat pumps, etc. However, laying pipes under a floor can considerably raise the overall floor height, so water-powered systems are most commonly used in new-builds or substantial renovation projects where an increased floor height poses fewer problems.

Floor materials that work best with underfloor heating

Almost any floor material can be used with underfloor heating, but those that work best have a high thermal conductivity. Higher conductivity means the floor will heat quicker, providing increased heat output and efficiency. Tile and stone surfaces work best with underfloor heating – however, wood, laminate, vinyl, and carpet can also be used. In each case, you should consult with the manufacturer first to check suitability.