The low-down on low-profile underfloor heating systems

25 Jul 2017

Discussions around the industry suggest that homeowners need no convincing of the merits of underfloor heating as it continues its increase in popularity, achieving steady sales growth of around 10% per year.  Underfloor heating delivers 10-15% greater efficiency from a boiler-driven system and is complementary to low temperature systems (e.g. heat pumps).  Add this to evenly distributed temperatures, controlled room by room, and you have something very attractive to customers.

There is a misconception that for a property to benefit from warm water underfloor heating, it must be installed at build stage, or follow expensive and disruptive excavation. Now however, thanks to new materials, new technology and greater knowledge, low profile and lightweight systems have been developed which are simple to install, while still providing excellent, efficient heating.

Modern low profile systems do not normally incorporate conventional insulation or screed, resulting in a product with a much greater field of application -i.e. in existing properties.  Without a sound understanding of the modern systems on the market today, and the benefits they provide, those considering integrating underfloor heating within a property may wrongly assume that their project is not compatible with the technology, or is simply too much work.

Low profile and lightweight underfloor systems, some only 18mm in depth, provide a range of alternative options, with some able to be fitted in a day.  Operating at a lower temperature, typically in the region of 50 degrees Celsius compared to radiators that operate at 70 degrees Celsius, water based underfloor heating produces a radiant heat, rather than convected, providing an evenly distributed ambient temperature throughout the room rather than “hot spots” and cooler areas.  Couple this comfort benefit with lower energy bills and you see why customer demand for underfloor heating is growing.

The system also lends itself to a ‘mix and match’ approach. Underfloor heating does not need to be installed in all rooms of a building, and screeded systems can be installed alongside low profile, and radiators giving total design freedom to the installer, and project manager.

With many different systems available on the market, it is important the correct one is specified for each project. Installers and specifiers should be assessing the space the system will be installed in, the required performance characteristics as defined by the heat source, floor construction and floor covering.

Perfect for renovations or when the floor of a property cannot be raised in height, low profile underfloor heating systems can be fitted to timber joists or floating floors. While most underfloor heating manufacturers will have their own selection of low profile systems, they can typically be split into six types:

Low section panel systems

Consisting of a gypsum fibreboard that has routes or grooves caved into it, the underfloor heating pipework is fitted into the board, resulting in finished depths of 15 to 29mm.

Low section grid/ levelling compound system

With levelling compound systems, the pipework and levelling is housed in a profiled plastic panel, some with an adhesive backing to aid installation, with a finished depth of 15 to 22mm.

Lightweight aluminium plate systems

A profiled polystyrene insulation panel designed to fit the pipework and aluminium plates with an intermediate layer of plywood, chipboard or gypsum fibreboard laid over. The finished depth tends to be between 43 and 68mm.

Lightweight foil faced insulation systems

A profiled polystyrene insulation panel with a bonded aluminium layer added. The pipework fits into the panels with an intermediate layer of plywood, chipboard or gypsum fibreboard laid over to accommodate the floor covering, with a finished depth of 25mm to 68mm.

Lightweight aluminium plate wood panel systems

A wood panel designed to take the underfloor heating pipework and aluminium plates with an intermediate layer of plywood, chipboard or gypsum fibreboard laid over it. The finished depth is between 15 and 36mm.

Lightweight aluminium foil wood panel systems

A wooden panel with a bonded aluminium layer designed to take the underfloor heating pipework with an intermediate layer of plywood, chipboard or gypsum fibreboard laid over to accept the floor covering. The finished depth tends to be between 15 and 36mm.

Heat sources

The heat source of the system also needs to be identified.  Although both a boiler and heat pump work perfectly with underfloor heating, it is important to match the system and heat source with the requirements of the property.  It is also important to realistically assess, how quickly the installation will need to be completed, the number of manifolds the system will need and any additional insulation requirements. 

In order to ensure a property has the most suitable system installed, it is imperative that designers, specifiers and architects have a solid understanding on the different systems available. Using BEAMA resources for the latest guidance and advice documents will ensure an efficient and effective installation, every time.  A guide to different floor coverings used with underfloor heating is due to be published soon with others on the way and right now you can download the guide to low profile underfloor heating systems here:

http://www.beama.org.uk/resourceLibrary/low-profile-guide.html

ENDS