If buildings could talk, they would ask for Infrared

Reduction of Condensation

Condensation caused by central heating
Condensation caused by central heating

Central heating works by warming the air around the heater, which creates convection currents that carry the warmth around the room. Convection insufficiently warms surfaces of objects in a room (Ardehali et al., 2004).  Warm air has a high capacity to hold moisture and when it meets a cold surface, condensation will occur. Central heating = Condensation and the chance of mould, fungus; wood rot and salt damp or flaking paintwork.

Infrared on the other hand warms the surfaces of objects without warming the air.  The relative humidity in the air consequently remains low and when the air meets a warm surface, condensation does not occur.

This is one of the primary benefits to buildings of Infrared Heating.

Reduction of existing damp

Because water absorbs heat specifically well at 3 microns and lower – Far Infrared – Far Infrared is also beneficial in drying-out dampness from buildings – either passively or deliberately.

Passively used, the infrared from a heater will begin to warm the masonry of a building. When masonry is damp, it absorbs and emits infrared poorly and air circulation actually needs to be encouraged to remove the evaporated water vapour.  As masonry dries out, the thermal reflectivity of the room also improves. This is because water in damp masonry initially absorbs the heat and does not emit the warmth back into the room, whereas dry masonry re-emits nicely. You may hear this being referred to as the “U value”: where a ‘low’ value is to be found in dry masonry and a high value in wet.

This therefore has application and value in historical buildings, for example, or hospitals, where the present of heat and damp together need to be discouraged. Infrared dries walls and plaster and preserves paintings and fabrics.

Deliberately used, Infrared heaters such as the Herschel Advantage IR range can be used for flood recovery purposes. The Far Infrared is better absorbed by the wet masonry over time and dries from the inside out.  Hotter heaters such as quartz and gas blowers are less efficient driers, because their harsher heat flash-dries the surface of the wall, creating a “skin” under which bubbles of water vapour then form, causing blistering of the surface of the masonry.

Preservation of fittings and materials

Use of Far Infrared in a building will not only dry out masonry and plasterwork over time, but is therefore also beneficial to wooden and metal fittings.

Up until the introduction of central-heating systems, the maintenance intervals for the contents and interiors of historical buildings were far-apart. This was because these buildings were typically heated by radiant sources of heat such as stoves or burners (as opposed to convection). After the introduction of central-heating systems, intrusive measures became necessary every few years to guard against mould, fungus, salt damp, surface contamination, subsurface rot, etc.

More elegant, less obtrusive and easy to install

From a design and “finishing” point of view, remember that infrared heaters come in many different designs. They are not just “heaters”. You can consequently mix form and function in a way never-before possible. For example, some Infrared heaters are mirrors; others are pictures which can be hung decoratively in hallways and rooms.

For public places with large atria, you can choose from a variety of attractive infrared spheres that can be suspended from the ceiling, or which can be free-standing in your reception area. Other panels are shaped to fit in the ceiling grid of offices and public places to provide heat unobtrusively.

Less obtrusive
Infrared heaters are less obtrusive than any other type of heater. All other types of heater – to some extent – require space of their own, forcing furniture and even use of the room itself to “fit around” the space occupied by the heater. This is not true for infrared panels which are typically mounted on walls out of the way of furniture and functional “use” of the room and when ceiling mounted are even more discreet.

Easy to install
Herschel Infrared heating has been approved for use in Grade-listed buildings because its installation requirements and impact are so small.

All you need to consider when installing infrared is:

  • Provision of an electrical source of sufficient capacity for the intended load;
  • Adequate strength in the surface where the unit will be mounted.

There are no requirements for fuel storage, pipe-work, flues or extractor fans or any additional insulation. This makes Infrared significantly easier to install than oil or gas boilers, heat pumps, underfloor heating etc.

Low / No maintenance

Infrared also has the considerable advantage of requiring no maintenance because it has no moving parts. As well as adding to the overall cost-savings case, it saves significant annual organisation. And unlike gas or oil boilers you won’t have to contemplate performing an entire re-installation every 10 years.

Summary differences to buildings: Convection vs. Radiant Heating

Convection Heating Infrared Radiation Heating

The effects of convection heating in a room
The effects of convection heating in a room

The effects of radiant heating in a room
The effects of radiant heating in a room
Damp air creates mildew and destroys masonry Objects and masonry stay dry and intact
Insulation necessary behind heat source and to prevent cold walls chilling the room No insulation necessary. Walls and other objects heat the room.
Temperature differences within the room cause draughts No heat layering and no draughts
Expensive to buy and operate, storage of fuel, flues / chimneys, Economical to purchase, and energy-saving operation, no flues or chimneys, no fuel tanks, easy to install
Moving parts require servicing and make product life uncertain No moving parts. Product life exceptionally long. No maintenance schedule so no interim expenses.
Costly to upgrade heat source (e.g. boilers, central heating system) Cheap to upgrade.
Specialist required to install If you can hang a picture, you can install an Infrared heater.


Ardehali, MM, Panah, NG, and Smith, TF. 2004. Proof of concept modeling of energy transfer mechanisms for radiant conditioning panels. Energy Conversion and Management 45 (2004) : 2005-2017.

Publisher: Herschel Infrared