The industry has developed a range of new applications for underfloor heating technology and these are likely to open up new revenue streams for contractors, says Tony Harbour
Conventional underfloor heating is now very much a mainstream heating option in the UK with proven pipework solutions working in partnership with renewable and low energy heat sources.

However, the continuing evolution of the technology and the demand from specifiers for ever more efficient and low energy buildings is creating a whole range of new, less conventional applications from chilled ceilings and thermally activated building systems (TABS) to industrial floor heating and underpitch heating.

High cooling loads and a growing need to deliver BREEAM Excellent ratings in new buildings are the main drivers behind the increase in specifications of chilled ceilings and TABS which even a couple of years ago would have been considered cutting edge in the UK. There is also a growing acceptance that the low energy, low maintenance principles which underpin underfloor heating can equally be applied to cooling.

Increasingly, fan coil units simply can't balance the cooling outputs and energy savings required so specifiers are turning to alternative solutions, in part because they have already been extensively proven across mainland Europe and in other parts of the world.

Chilled ceilings are essentially radiant chilled plasterboard panels with loops of PE-Xa pipe pre-fitted. They can be used in place of standard suspended ceiling panels to provide a simple, effective and concealed cooling solution for commercial buildings.

There is a real buzz surrounding this technology and, from a contractor's perspective, I believe we are on the cusp of a massive new opportunity. In terms of design, the main issues surround the integration of the pipework with the other ceiling elements such as lighting, sprinklers and audio systems. However, in installation terms, it is very straightforward because the pipework is pre-fitted to the ceiling panels and the only real concerns are in ensuring that the jointing is carried out correctly and that there is constant vigilance to ensure that no pipework is cut during the installation of other services.

In contrast, TABS is a concrete temering system which embeds PE-Xa pipework inside a concrete floor or ceiling slab to transform it into a huge thermal store to absorb high heat loads. Cooling or heating water circulates through the arrays of PE-Xa pipe and pre-conditions the temperature of the concrete mass creating the potential for virtually limitless storage.

When used in conjunction with a supporting ventilation system, TABS can provide an energy efficient and cost effective alternative to full air conditioning strategies. The supporting ventilation system can be designed just to provide the required fresh air supply, reducing both the initial investment and the running costs

Used extensively overseas
Like chilled ceilings, TABS is being used extensively overseas, with a high profile installation recently completed in the Vodafone Site Solutions Innovation Centre in South Africa and, in the UK, it has just been specified in the new Tate Modern building to be built in Southwark, London.

From a design perspective, TABS is much more complex than chilled ceilings because the output and flow needs to take into account the mass of the concrete itself as well as the final floor covering. However, as long as it is co-ordinated correctly between the design team and contractor, it can be installed in virtually any concrete structure - and can even be built using off-site techniques in precast slabs.

There is evidence that both chilled ceilings and TABS score well in terms of both comfort levels and energy savings. An independent dynamic modelling study carried out at the University of Sacramento in California during 2010 evaluated the relative overall comfort levels delivered by seven different combinations of heating and cooling solutions including air handling units, floor heating and cooling, chilled ceiling and TABS.

The best performing solutions for occupants were chilled ceilings and TABS, with air handling units ranked lowest in terms overall thermal comfort. The same dynamic modelling study evaluated the final energy demand for heating and cooling of the same systems and concluded that TABS had the lowest annual requirement at just 108kWh/sq m, almost 60kWh/sq m less than the requirement of the air handling units, which were the highest.

Industrial floor heating is another real potential growth area for contractors with more and more specifiers choosing an underfloor heating solution with a renewable heat source rather than fan coil units or gas-fired heating systems. In aircraft hangars, warehouse and distribution facilities, for example, the benefits of a low energy, low maintenance system which places only very low loads on the heat source increasingly outweigh what are generally higher installation costs.

With so many viable opportunities available, now is an exciting time to be involved in the underfloor heating market.

The author is technical specifications manager at REHAU Underfloor Heating