Underfloor Heating

The main benefits of Underfloor Heating (UFH), when compared to conventional radiator heating systems, can be summarised as follows:

 

Superior Comfort

  • Floors without carpets become comfortable and cosy when heated by modern hydronic means. Materials such as tiles, marble, and natural stones, which would normally be cold to the touch, become pleasantly warm with heated floors.
  • Heat is concentrated at floor level, where it is needed, with minimum temperature varients; in fact, modern radiant floors achieve the closest temperature distribution profile to the theoretical human comfort profile; warm feet and cool head.
  • Floor heating provides an even air temperature across the room and therefore, increases all round comfort; without low level and local hot spots, associated with radiator systems.
  • Heat transmission from the heated floor more nearly matches the percentage radiant/convective mix that is lost from the human body, resulting in better balanced heat transfer between the person and the heated surface.

 

High Efficiency 

There are a number of factors that make UFH the most appropriate energy efficient form of heating, including:-

  • Floor heating does not create the strong convective currents associated with natural and forced convection heat emitters, it provides a more uniform temperature and air pressure within the indoor space, resulting in reduced heat losses.
  • Approximately 70% of the floor heat emission is in the form of radiant transfer, which heats bodies, objects and the internal building fabric surfaces without directly warming the air. This heat exchange increases the room’s mean radiant temperature MRT, which implies that a lower air temperature, in comparison to convective systems, will apply when determining an equivalent Operative Temperature. A value of 1 to 2'C reduction in room air temperature is commonly achievable for UFH, when compared to radiators, for use in heat loss calculations.
  • The low flow water temperature, usually between 35 and 50'C, makes this form of heating highly suitable for coupling to energy efficient heat sources, such as condensing boilers, heat pumps, solar panels and heat recovery systems.
  • UFH, with solid floor constructions, provide a large thermal storage capacity giving rise to steady energy demands and therefore reduced boiler cycling.
  • The use of sophisticated controls like the range of weather compensators and advanced thermostats, will further reduce running costs.

In general, figures between 5% and 50% are often quoted for energy savings when compared to traditional radiator and warm air heating systems, actual savings will depend on many factors. Buildings with high floor to ceiling dimensions tend to produce the greater savings due to reduced air temperature gradients.

 

Redecoration, maintenance and cleaning costs 

UFH has a long maintenance free life with just the manifold exposed above the floor. The embedded pipe, to comply with European Standards, is manufactured to realise a life expectancy exceeding 50 years. Additional benefits include reduced decorating maintenance costs:-

  • Rooms are more easily decorated without any obstructions caused by heat emitters.
  • There is no wall discolouration, which is often caused by wall mounted radiators.
  • There is no possibility of accidental or intentional damage to the heat emitter.
  • No risk of damage to floor covering due to leaking radiator valve connections.
  • Nothing to clean or paint with significant reduction in maintenance time and costs.

 

Space allocation and aesthetics 

  • Placement of furniture is not limited by location of the heat emitters and net useable floor area is increased; in fact freedom of room layout is more or less unrestricted.
  • There are no unsightly radiators or other heat emitters, or exposed pipe runs and pipe.
  • The size and style of curtains are not restricted by under window radiators.
  • The system can be totally invisible and vandal proof to occupants with the addition of discreet room controls.

 

Health and safety

The reasons for choosing UFH could be justified for some people solely on health and safety grounds. The advantages of not having an exposed hot surface in nursing homes, primary schools, hospitals and other public buildings is readily apparent.

  • The floor surface temperature is designed to be less than 29'C, way below the 43'C touch temperature that is stipulated by guidance standards, for rooms that may be occupied by young children and/or the elderly. If not using UFH, the requirement is normally achieved by the installation of relatively expensive low surface temperature radiators operating on a standard boiler water flow temperature of around 70 to 80'c Alternatively, conventional radiators operating on reduced water temperatures with radiators being oversized to achieve the required heat output. In both instances the actual cost differential, when compared to an UFH installation, is considerably reduced.

Other health and safety benefits include:

  • Floor heating reduces relative humidity levels especially at floor level. This helps inhibit the growth of house dust mites as high humidity levels are required by the mite for its survival, it is a known contributor to the increased proliferation of asthma and othe allergens.
  • Because convective currents are weak, there is a general reduction in the circulation dust and other particles.
  • There is no risk of an occupant being injured by potentially hazardous wall projections or dangerous hot surfaces.

 

Dry floors

UFH can significantly increase floor drying times and reduce slip risks in frequently wet floor areas, e.g bathrooms, shower rooms, wet rooms, swimming pools.

Radiant Control can design systems to acheive minimum floor temperatures to dry floor and maintain comfort.

No noise

The plastic pipe in UFH will not resonate or amplify sound, this is a common problem for conventional systems utilising metal pipe work where noise can be transmitted around the entire system.