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Installing Underfloor Heating – Tips and Hints


Installing Underfloor Heating

Tips and Hints


All underfloor heating systems, whether “wet” or “dry”, essentially work in the same way. Heat energy – derived from warm water flowing through pipes, or from electrical heating cables, or mats, beneath the floor – is radiated upwards into the space above.

This creates a more natural temperature gradient than traditional radiator systems, which tend to heat the space immediately below the ceiling
first and, because the entire surface area of the floor is used for heating, less heat energy per unit area is required.

baby crawling on tiled floor This effectively means that not only can comfortable conditions be achieved at lower air temperatures – typically 2°C lower – than with traditional radiators, but also that underfloor heating systems can be more energy efficient, and economical.

Types of Underfloor Heating


So-called “wet” underfloor heating systems circulate warm, rather than hot, water – typically at a temperature of around
50°C and therefore much cooler than a traditional radiator, which may have an operating temperature of
80°C or 90°C – around a series of continuous pipe loops beneath the floor.

Indeed, not only may a wet underfloor heating system be 30% more efficient than a traditional radiator system
and therefore economical as the main form of heating in your home, but it may also free wall and floor space otherwise occupied by radiators, so that you can design your
interior and position your furniture exactly as you desire.

Gas, oil and solid fuel boilers can all be used as a source of heat for a wet underfloor heating system – although condensing boilers are usually the most efficient in this context – and integrating a system with your existing plumbing, including radiators if you do not wish to have underfloor heating throughout your home, is a definite
possibility. Be aware, of course, that like any form of heating system, wet underfloor heating will only work efficiently if your home, including the sub-floor,
is properly insulated against heat loss.


So-called “dry”, or
electric underfloor heating systems, on the other hand, are available in the form of basic heating cables, sometimes loosely woven into mesh mats, flat, or ribbon, cables, or heating films.

electric under floor heating or dry heating

Electric underfloor heating systems, on the whole, allow a room to reach the required temperature faster
than wet systems, because they are direct heat sources, but may also be anything up to 40% more expensive to run than wet systems.

Some less expensive electric systems may be unsuitable for installation beneath
engineered or laminated, wood flooring, but ribbon cables which operate at a temperature as low as 30°C, are
available and these can be installed without danger to the colour, texture, etc. of these and other sensitive floor coverings, such as carpet, or linoleum.

Underfloor Heating Installation

The pipework installed as part of wet underfloor heating
systems nowadays, is typically high quality – PEX (the generic name for polybutylene, or polyethylene) and Alupex™ (a five-layer composite of PEX and aluminium) are popular materials
and are continuous, so there is no danger of leaking from joints.

Wet underfloor heating systems are, however, best suited for inclusion in newly built
homes because of the disruption and expense involved in taking up the floor(s) of an existing property.

Repair, or maintenance, of wet underfloor heating systems, if it is required, may prove troublesome and costly, so reliable materials are a necessity. A wet system also requires space for timer controls, individual valves for each room, etc., but these can often be positioned together in a single location, such as a cupboard.

Electrical underfloor heating is more appropriate for renovation projects in existing properties, as heating cables, or mats, are laid on top of the existing sub-floor, or insulation board, such that the height of the floor need only be raised by a few millimetres, at most.

Electric underfloor heating is easy to
install and inexpensive, especially if you wish to heat a single room, such as bathroom, for short periods. You can, of course purchase electrical floor heating online, and fit it as a DIY project, but you should secure the services of a qualified
electrician to connect the cables, or mats, to the mains electricity supply.