A far more sustainable answer than hiring prefabricated portable classrooms, the new building provides students with a practical example of sustainability in action. In accordance with the performance requirements of part L of the Building Regulations, the fully insulated building conforms to simplified building energy model (SBEM) calculations for low energy use and low carbon emissions.
The new building comprises three classrooms dedicated to food science, textiles and psychology. Designed to meet the school brief and delivered within a school year, the time needed on-site was just 15 weeks, so disruption to the school was minimised.
Kingsbury School headmaster, Simon Cotton, noted, “Sustainability was one of our most important criteria. Tenders requests specified our space needs and target carbon emissions. Smart Space came back with a competitive proposal that balanced the use of innovative environmentally friendly technology with more conventional approaches, to give us a practical and highly energy efficient building that was still within budget.”
To meet the sustainability target special features include: a secondary internal lining with 40mm insulated foam board to reduce U values, an insulated floor slab to reduce heat loss to the ground and underfloor heating supplied from an air-source heat pump. The heat pump uses the atmosphere as a heat source, using electrical power only to operate the pumps and fans that circulate air and the transfer fluids so that the heat energy delivered can be up to three times the power drawn. A high efficiency boiler provides domestic hot water and lighting is by energy efficient LED’s.
The Smart Space system building is based on a light weight steel frame, with insulated infill panels. Light buildings require far less groundwork, making them less expensive and quicker to erect than conventional buildings. The whole project was completed for £200,000, funded from within the school’s own budget.
Smart Space was the main contractor, supplying the main structure and working with consultants ARV Design to optimise insulation and building services to meet the environmental targets cost effectively. Speaking for ARV, Ross Vintner said, “The target carbon emissions are given in the SBEM requirements. We undertook initial calculations, based on high levels of insulation and conventional technology such as electric space heating but these would have far exceeded the target. Revised calculations, based on the use of an air source heat pump and underfloor heating enabled us to reduce this substantially to meet target emissions. Other technology, such as the use of solar collectors for water heating and air-conditioning for summer cooling was considered, but rejected as less cost effective than the measures provided.”
Simon Cotton concluded, “We will welcome 35 new sixth form students in September, working toward our eventual aim of 150 post 16 students. The new building is clean, bright and very practical. This is the second Smart Space building on this site, following a sports hall that they erected two years ago. Site works were, as before, well-coordinated and the whole building delivered quickly and as promised.”
Heat pumps that extract heat from the environment for use in space heating are a proven technology that is being more widely used. Based on the same principles as a domestic refrigerator, the heat capacity of a special heat transfer fluid is increased by passing this through a valve to create a phase change from liquid to gas. This reduces significantly the temperature of the transfer fluid, enabling it to collect heat from the outside air as it passed through the external heat exchanger. This process can harvest energy even at low outside air temperatures.
The warmed transfer gas is then compressed, tuning it back to liquid and concentrating the heat energy, before this passes through a second heat exchanger that transfers the warmth into the water circulating in pipes below the school floor. Air, ground or water may be used as the environmental heat source, but air source heat pumps have lower complexity, cost and are easier to install.
Antony Hunt, Managing Director, Tel. +44 (0)1827 330000 Fax. +44 (0)1827 898600
E-mail: email@example.com Web: http://www.smart-
Smart Space, Manor House Farm Business Park, Dordon Hall La, Grendon, Warwickshire, CV9 2EX
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