Underfloor heating (UFH) is an advanced heating system that is gaining popularity in residential buildings due to its efficiency, comfort, and aesthetic advantages. Unlike traditional radiator-based systems, underfloor heating provides consistent warmth across a room by utilising pipes embedded beneath the floor surface. The water is heated by a boiler, heat pump, or solar thermal system and heat is distributed evenly across the room.
This report explains the working mechanism of underfloor heating and highlights its benefits over conventional radiators to help meet the requirements of modern buildings legislations. This is particularly important as 60% of a homes’ total energy consumption is through its heating demand.
In many cases, new homes are required to produce much less carbon than current homes. This means that many home owners will chooses to have their home heated via a heat pump
Underfloor heating will typically improve the efficiency of the heat pump by 30% over radiator systems. Underfloor heating will reduce consumers bills, improve comfort, and improve house saleability.
Specification of underfloor heating starts with the floor build up. Heat outputs vary depending on flow temperature, pipe size, spacing between pipes and floor build-up and smart controls help to make an efficient heat pump with underfloor heating system
Benefits over radiators
Unlike radiators, which despite their name are actually convection heaters and create localised heat near the unit; underfloor heating ensures uniform warmth throughout the room by radiating heat from the entire floor surface.
Underfloor heating (UFH) operates at lower temperatures (typically 30-45°C for wet systems and 40-50°C for electric systems) compared to radiators (which often require temperatures above 60°C). This improves efficiency and reduces energy consumption. The expectation is that radiators result in that UFH operates at 1-2ºC lower air temperature. This will result in a reduced heat demand of 10-20%, saving energy and reducing bills
Underfloor heating is particularly well-suited for use with heat pumps due to its ability to operate effectively at lower temperatures. Heat pumps, such as air source and ground source heat pumps, work most efficiently when supplying heat at lower flow temperatures, which aligns perfectly with the operating range of underfloor heating systems. The large surface area of UFH allows for gradual and consistent heat distribution, reducing the workload on the heat pump and enhancing overall energy efficiency. Additionally, combining UFH with heat pumps can significantly lower carbon emissions and running costs, making it an ideal solution for eco-friendly and energy-efficient homes.
The radiant heat from UFH rather than convection heat from radiators warms people and objects directly, preventing cold spots and providing a more comfortable indoor climate.
Traditional radiator sizing has been for 20ºC indoor, 70ºC flow temperature ∆T 50ºC. Part L indicates 45ºC flow temperature for new build, making the ∆T 25ºC; this doubles the required radiator size for the same output. Underfloor heating eliminates the need for bulky radiators leaving architects and designers greater flexibility in room layouts and furniture placement. This allows for more open-plan living spaces, improved aesthetics, and better utilisation of available square footage. Additionally, eliminating radiators enhances wall space, making it easier to install large windows, maximise natural light, and create a modern, streamlined interior. These advantages make UFH a preferred heating solution for contemporary home designs where efficiency, comfort, and visual appeal are key priorities.
Wet underfloor heating systems have fewer moving parts than traditional radiator-based systems, leading to reduced wear and maintenance costs over time.
Unlike radiators that circulate dust and allergens through convection, UFH minimizes air movement, making it a healthier option for allergy sufferers.
Benefits of radiant heating over convection heating
Underfloor heating primarily relies on radiant heat transfer, which offers several advantages over traditional radiators (convection-based heating systems).
More efficient heat transfer: Radiant heating directly warms objects and people, reducing heat loss compared to convection systems, which rely on warming the air.
Reduced heat stratification: Convection heating causes warm air to rise to the ceiling while leaving lower areas colder. Radiant heating maintains a more uniform temperature from floor to ceiling.
Better air quality: Since radiant heating does not rely on air circulation, it minimizes the spread of dust, allergens, and other airborne particles, improving indoor air quality.
Lower energy consumption: Because radiant heat is more effective at making a room feel warm at lower temperatures, less energy is required to maintain comfort, leading to lower heating bills.
Enhanced comfort: Radiant heat creates a more natural and comfortable warmth, similar to the heat from the sun, without the dry air effects often caused by convection heating.
Silent operation: Unlike radiators, which may produce noise due to water flow and expansion, underfloor heating operates silently, contributing to a more peaceful living environment.
It is misunderstood generally that UFH will only work with ‘tiled floors’. Whilst tiled floors provide the most efficient flooring for heat transfer, other floor covering can also be used to meet architectural requirements. If so, it should be included in the design calculation stage of the system allowing for application in all rooms in the house including upstairs where in some homes carpets are still preferred. See table below:
|
Expected heat outputs per m2* |
Flow temperature (∆T 10 ºC) | ||||
| Floor finish | Thickness | 55 ºC | 45 ºC | 35 ºC | |
| Tiled | 10 mm | 146 W/m2 | 95 W/m2 | 45 W/m2 | |
| Vinyl | 6 mm | 117 W/m2 | 87 W/m2 | 41 W/m2 | |
| Hardwood | 12 mm | 105 W/m2 | 69 W/m2 | 33 W/m2 | |
| Carpet (1 Tog) | 8 mm | 95 W/m2 | 62 W/m2 | 29 W/m2 | |
*Note the above outputs should be used for guidance only and variations in temperature, floor finish, K-value, thickness, pipe type, pipe spacing and materials will change the output. Calculations are made for rooms with a room temperature of 21 ºC. Please request exact outputs for your floor finish from Wavin's technical team.
Underfloor heating is a highly efficient, comfortable, and aesthetically pleasing alternative to traditional radiators. Its ability to distribute heat evenly, improve energy efficiency, and offer health benefits makes it an attractive choice for homeowners. The system's compatibility with heat pumps further enhances its sustainability and cost-effectiveness.
Additionally, its use of radiant heating provides significant advantages over convection heating, including better energy efficiency, improved air quality, and superior comfort.
For new build homes, the space-saving benefits of UFH allow for greater design flexibility and a modern, open-plan living experience. Although initial installation costs may be higher, the long-term savings and advantages in comfort and design make underfloor heating a worthwhile investment.
Working with a supplier who really understands underfloor heating and controls is an enabler to ensure you achieve carbon reductions. Please contact us to discuss your next project.
