Showing the way to low carbon
Far exceeding the requirements of the Building Regulations — Warmafloor’s new headquarters shows what buildings of five years hence, or more, could be like.
Warmafloor’s new headquarters substantially outperforms Building Regulations that came into force after it was designed. And managing director Mike Lamb wants to share his experiences with the setting up of a sustainable energy centreWith a steady tightening of Building Regulations planned over the next few years to continue progress in reducing the carbon footprint of buildings comes the need for a wider understanding of how these requirements can be met. The 2006 Building Regulations are more demanding than those of 2002, which, in turn, required buildings to use less energy than previous regulations. So how can those new energy standards be met? A typical example of the type of commercial/ industrial building that can be found throughout the country is the recently opened headquarters of Warmafloor at Fareham in Hampshire. The construction of this building is typical of many others, but it is serviced in such as way as to reduce its energy consumption and carbon emissions by at least 60% compared to other similar buildings. It is to be compared with other buildings designed to 2002 Building Regulations and will also represent about 40% better than the 2006 regulations require. The services installed by Warmafloor have been operating for nearly a year, and the building is being monitored by BSRIA to produce an independent analysis. When the 2006 Building Regulations were being devised, leading lights urged the industry to look to better them rather than merely comply with the minimum requirements. This is certainly what Warmafloor has achieved, showing today how such buildings could be designed five years hence or so. Opportunity
Mike Lamb is managing director of the company and explains, ‘We needed larger premises, and I saw this as an opportunity to take up the sustainability challenge — not just to save on energy costs, but also to show others what could be done with affordable technology in a building of this type. ‘The Government is looking for a 20% reduction in carbon emissions by 2020, but I believed that if we took an integrated approach then at least 60% reduction was achievable, beating the Government’s future carbon-dioxide target for 2050.’ The shell of this 2500 m2 building is a standard ‘shed’ with a low thermal mass having a response time of only around 3 h — so thermal mass cannot be used to temper the internal environment. Among the technologies used are heat pumps and underfloor heating. Individually, each could reduce carbon emissions by 20%, but by using ground-source heat pumps to heat and cool the building, savings of rather more than 40% are being achieved. Ground-source heat pumps provide heating, cooling and hot water. Heating and cooling is generally provided by two heat pumps using R404A designed for an off temperature of 30°C with an on-temperature of 12°C and achieving a COP of six. The heat source is from 4 km of ‘slinkies’ under the car park and installed at the same time as the machinery was on site to lay the car park, minimising installation cost. Likewise, 10 m2 of solar photo-voltaic panels were installed on the roof at the same time as access equipment was on site for cladding the building. Radiant temperature
One of the benefits of large surface areas being used for heating and cooling (underfloor and ceilings) is that comfort can be achieved in heating mode with an air temperature of 18°C and in cooling mode with an air temperature of around 24°C — owing to mean radiant temperature being more important than with other types of heating and cooling. This approach to cooling is very effective; Mike Lamb says, ‘Even on the hottest day, with all our people and computers generating heat, the building can be chilled to the point of being too cold simply by using energy from under the car park via the heat pump.’ The building’s long-term environmental credentials are enhanced by using polybutylene pipe embedded in the floor screed. This material can be recycled, unlike PEX. Not only has waste material from the initial installation been sent back to the manufacturer, but polybutylene pipe can be separated from the screed at the end of its life. Natural ventilation is quite simply provided by opening windows and trickle vents. However, this ventilation is support by an air-handling unit controlled by carbon- dioxide sensors. Only when carbon-dioxide concentrations exceed 800 ppm does the air-handling unit operate. For thermal efficiency, the AHU incorporates a cross-flow plate heat exchanger. Solar energy is used to generate domestic hot water. To reduce the demand for mains water, rainwater is collected from the roof and stored in a 12 000 litre tank for tasks such as flushing toilets and cleaning cars. To offset carbon used in construction, over 200 silver birch trees have been planted outside the south-facing meeting rooms to provide shading in summer while letting maximum light into these rooms in the winter. Wind turbine
One source of renewable energy that Mike Lamb has not yet been able to install is an 850 kW wind turbine to generate electricity for the surrounding business estate. The electrical connection is already in place, but there are problems obtaining planning permission. Without the enthusiasm of Mike Lamb, Warmafloor’s new headquarters would have very likely been a standard industrial/commercial building. But his enthusiasm does not stop there. Having become thoroughly acquainted with low- and zero-energy technologies, he has set up a sustainable-energy centre in a wing of the building, with display areas and seminar rooms open to all building and services specifiers. There is more information on the SEC web site, where you can book a visit. On show in the SEC are technologies from 16 companies, including heat pumps, condensing boilers, heating manifolds, controls, daylight tubes, underfloor heating and cooling, chilled ceilings, electric underfloor heating, solar panels, underfloor pipe, ground recovery pipe and controls. Let's give Mike Lamb the final word on Warmafloor’s new headquarters. ‘We’ve only used affordable and proven technologies, but I'm being told we’ve created a building which performs in an “extraordinary” way.’