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Poured-concrete walls, dark, musty corridors. No sunlight, no laughter 鈥� and a dreadful, if functional, line in cast-iron column radiators. Who said school days were the best of your life?

Step forward the new generation of educational buildings. Not only designed to show the general populace how seriously the government takes its commitment to a low-carbon economy. Not solely constructed to educate future generations on the importance of sustainability. But also built to provide kids with the kind of bright, breezy, contemporary environment where they might actually want to learn.

The new Michael Tippett School in Lambeth, south London, is a class example. From its sunlit entrance lobby to surprisingly airy classrooms, natural daylight works hand in hand with natural ventilation. A searing, sticky June day is quickly replaced by a pleasant coolness as Durgesh Chadee of structural and services engineer Gifford begins an absorbing guided tour from the double-height foyer.

The special needs school is the first to be completed under the 黑洞社区 Schools for the Future (BSF) programme, to which the government has pledged a staggering 拢45bn on renovating and rebuilding schools in England and Wales within the next 10-15 years. The scheme aims to reduce energy use by at least 60% against the 1990 baseline. Not a bad proposal when you consider schools alone are responsible for 15% of energy used in UK public and commercial buildings.

In the three years since BSF was launched, the issue of carbon emissions has surged to the top of the government鈥檚 agenda. The present goal is to provide zero-carbon new schools by 2016.

The school was developed in record time. M&E contractor Goldhall Electrical was on site for just six months, in a contract worth 拢1.4 million. Pupils moved in on schedule this February.

鈥淭he old Michael Tippett School was demolished and the kids didn鈥檛 have anywhere to go, so it was all constructed very quickly 鈥� within nine months in total. It was a challenge for everyone. The m&e contractor hadn鈥檛 dealt with many school projects before, so it was a challenge for them too. That鈥檚 why we鈥檙e all proud of this one,鈥� says Chadee.

Despite the timescale, the project was a traditional build, with all m&e work carried out on site.

鈥淭here鈥檚 always the cost element with prefab, and I think that, because the m&e team was in early enough, they didn鈥檛 need to go down that avenue. The major kit is localised in a single plant room 鈥� just two boilers and the combined heat and power system. The rest is simple.鈥�

The client has its own maintenance team, though current discussions with both Gifford and Goldhall may lead to future maintenance contracts.

In full flow

To design and install the natural ventilation system that lies at the heart of the Michael Tippett School鈥檚 environmental standing, Gifford and Goldhall Electrical had to be in sync with the architects from early on.

鈥淚f the building fabric and the form aren鈥檛 right from day one, you might as well forget natural ventilation,鈥� says Chadee. 鈥淎rchitects can be very precious about their facades, and it takes a lot of discussion to get natural ventilation right. Luckily, with Marks Barfield architects that went really well. They were up for a low-energy building.鈥�

The school has a lot of exposed mass. In the classrooms there are no false ceilings, so all cabling is surface-conduit.

鈥淚t isn鈥檛 recessed, so we get a good degree of thermal mass. In the summer months, we just cool the fabric at night, then use that cooling during the daytime,鈥� explains Chadee.

The ceilings are also high and work well with the natural ventilation system.

鈥淚鈥檓 working on projects that have low floor-to-ceiling heights, and we can鈥檛 make natural ventilation work. You just don鈥檛 get the heat to rise up,鈥� says Chadee.

鈥淚鈥檓 working on another school that is a refurb project, and we have to assist the natural ventilation by introducing fans to help the air blow through.鈥�

Even the Michael Tippett School had its share of problems. The sports hall design had to be changed from a naturally ventilated scheme to a mechanically ventilated one.

鈥淲e just couldn鈥檛 fit enough louvres to make it work,鈥� admits Chadee.

Gifford commissioned Ashdown Controls to design an advanced building management system for the school.

鈥淭he clever thing is the interaction between the underfloor heating and the natural ventilation,鈥� says Chadee, with some pride.

Architects can be very precious about their facades and it takes a lot of discussion to get natural ventilation right

鈥淚f in winter you open the windows, you have a real problem. The underfloor heating won鈥檛 be able to cope with heating up the building. But the system is set up to bring on an audio alarm if the space isn鈥檛 getting up to temperature quickly enough, so people will be warned to shut windows.

鈥淢ost schools have the heating running with the windows open, but they end up having a big energy bill.鈥�

The school鈥檚 BMS network is based on the latest Trend IQ3xcite controllers, which feature web capability and can be accessed from any personal computer.

鈥淭his gives Lambeth increased flexibility when it comes to remote site management,鈥� explains Chadee.

The current intention is to regularly monitor all the BSF buildings in London.

A 黑洞社区 Bulletin guide recommends that a guaranteed amount of fresh air 鈥� in this case three litres per second per person 鈥� should be supplied. The team decided to achieve this by using motorised metal louvres at both the front and back of classrooms, to ensure good levels of cross-flow ventilation. These vividly coloured louvres shade ambitiously glazed classrooms and, on the outside, provide the school with its distinctively playful, cheery character.

鈥淚t鈥檚 not a mainstream school, and that certainly helps as well, because we don鈥檛 have that many pupils in each classroom. It鈥檚 a different story when you have 30 pupils in every room. Here we only have 10 to 15,鈥� adds Chadee.

Value engineering

Along with the ventilation system, other sustainable features include sedum roofing and a Dachs mini gas-fired CHP unit, installed by Goldhall. With the use of low/zero-carbon (LZC) technologies, Gifford has predicted a 13.4% saving on carbon emissions. Michael Tippett is also one of the first UK schools to receive a BREEAM 鈥榲ery good鈥� rating.

At the design stage, the team decided to use a combination of carbon dioxide and temperature sensors to regulate classroom environments. When the design was developed by the contractor, however, plans for CO2 sensors were discarded.

鈥淭his was primarily down to cost. Value engineering was needed to bring the project back to budget,鈥� explains Chadee.

鈥淭here wasn鈥檛 that much cutting on the services side. We did have to change our selection of light fittings. We had to use different manufacturers to the ones we鈥檇 had in mind in order to keep the costs down. But with regards to the quality of the installation, I don鈥檛 think we missed out too much.鈥�

The majority of the school鈥檚 lighting, however, is purely PIR-controlled, contrary to original specification.

鈥淒aylight sensors had to be omitted, as we made the decision to stay within budget, but school management also comes into it: teachers will turn lights off.鈥�

The approach paid off. The project was completed well within budget at a total cost of 拢7.4 million.

As Michael Tippett is a specialist school for disabled pupils and those with learning difficulties, the m&e team had to consider a range of special requirements. Hoists are prominent throughout the building, which also requires a large quantity of power points so that wheelchairs can be conveniently recharged.

Metal conduit was used throughout the installation, as pupils are likely to damage plastic.

The underfloor heating system has the added benefit of removing the need for radiators, which have the potential to cause injury.

Match changes

The very fabric of the building also takes its occupants into consideration. Free-standing, laminated-timber columns bring the practical benefit of flexibility. As exterior walls and internal partitions are disengaged from the structural frame, they can be easily adapted if the school鈥檚 future requirements or student intake change.

Chadee, however, is secure in the knowledge that modifications to services or design will not be required for any other reason. It is the first BSF project that he has been involved in from start to finish, and the first school he has delivered that passes the new Part L requirements by some margin.

鈥淭his building has been designed to stand 30 years with no need for changes or extensions,鈥� he says with assurance. 鈥淎nd we are confident that it will stand the test of time.鈥�