This contractor has led by example by cutting carbon emissions by two-thirds at its new headquarters

Winner: Fitzpatrick Head Office, Fitzpatrick

When Fitzpatrick moved to its new headquarters, it managed to cut its carbon emissions by 70% – even though its floor space had increased by more than a third. This impressive feat was achieved through rigorous attention to detail in every aspect of the design process. Twenty three tonnes of carbon has been saved through ground-source heat pumps; four tonnes through a solar panel array; 16 through an “intelligent power supply”, which automatically shuts down non-essential equipment – the list goes on. Water saving measures have been taken very seriously in this scheme, which unsurprisingly won a BREEAM “excellent” rating. Rainwater is collected from the roof, stored beneath the visitor parking and pumped back into the building to flush the toilets. And leak detection alarms have also been fitted. Landscaping in the grounds has created an attractive area for wildlife and boosted the number of species of flora and fauna fourfold. The firm has also worked hard to cut car journeys at its new office block. Cycling racks are provided and the building has a gym, onsite print facility and video conferencing technology to reduce the need for staff to leave the office. Fitzpatrick is determined to keep cutting its carbon footprint and this building has helped it make leaps and bounds in this respect.

Runners up

Adelaide Wharf, Hackney, Waterman Group

This scheme from developer First Base was built under the London-wide initiative, the government-backed programme that enables key workers to buy their own homes. Affordability was a key priority here and so no renewable technologies were used. Even so, the 147-apartment block, designed by Alford Hall Monaghan Morris, has carbon emissions of just 19.5kg/m² a year on average and it has picked up an “excellent” Ecohomes rating. Good insulation, low-energy lighting and a brown roof - part of the sustainability strategy from Waterman Group - all contribute to the building's low carbon footprint. Heating is provided though low emission condensing boilers and greywater is collected through a central system to water the garden. The development was built close to major transport hubs to encourage residents to ditch their cars and almost all the homes have cycle storage.

Advanced Manufacturing Research Centre with Boeing, Bond Bryan Architects

Bond Bryan Architects has always been ahead of the game on the environment - it established an in-house sustainability team more than 10 years ago. So it is no surprise to see the Advanced Manufacturing Research Centre at the University of Sheffield, designed by the practice, scoring highly on green issues. The £45m collaboration between the aerospace industry, government and academic institutions is zero carbon and has been rated “excellent” by BREEAM. Staff health was at the top of the agenda in the design process. Ninety eight per cent of the building's floor space is naturally lit, all office space is naturally ventilated and an engineering system has been installed to cut microbial contamination. Renewable energy is sourced through wind turbines and ground-source heat pumps. Other initiatives include landscaping around the site, which is a reclaimed open cast mine.

Exwick Heights Primary School, Exeter, Bauder

This project team was charged with building a low-energy school that would sit comfortably in a greenfield site outside of Exeter. As a result, the two-storey building is tucked into the hillside contours to minimise its visual impact. The lion's share of the heating for the 2,800m² development comes from gas-fired condensing boilers and the whole scheme is passively ventilated. A green roof - produced by Bauder itself - has been included to boost plant and bird life, provide extra insulation and teach pupils about sustainability first hand. And surface water drainage is dealt with by a sustainable urban drainage system, which channels the excess water into a pond. A key feature of the school is flexibility - lightweight internal partitions mean classroom shapes can be easily changed if necessary.

Howe Dell School, Hatfield, Mace Group

This school in Hertfordshire is the first building to use a new technique that allows heat energy to be stored up in summer and released in winter. Energy from the sun is captured via a network of pipes beneath the school playground, stored in computer-controlled thermal banks and then pumped out in the colder months. The scheme, designed by Capita Architecture and built by Mace, has a green roof, solar thermal water heating, solar panels and a wind turbine, which exports surplus electricity back to the grid. The building is also surrounded by paths for walking and cycling to encourage staff and pupils to use eco-friendly transport. The school, which has won praise for its eco-curriculum and even set up an “eco-squad” to look for ways to improve sustainability, has been selected as one of eight projects to be used in the development of the BREEAM for Schools initiative.

NG Bailey headquarters, Strathclyde, NG Bailey

NG Bailey set out to prove a point with the construction of its new Scottish headquarters. It wanted to show that normal office buildings could be made sustainable without breaking the bank. The result is its BREEAM “excellent”-rated building in Strathclyde, which is on course to cut carbon emissions by 75% and save £51,500 in operation costs a year. At that rate, the firm will make back its extra investment within 10 years. Striking features include sun pipes to take daylight from the roof to key areas of the building and photovoltaic windows, where solar cells are embedded between panes of glass. The project met some challenges on the way - such as building a 120m-deep ground-source heat pump on a fault line - but NG Bailey is nonetheless evangelical about its methods and is encouraging other firms to re-specify future office projects.

Watford Leisure Centres, Max Fordham

These two schemes in Watford have challenged the assumption that leisure centres have to be energy-intensive. Swimming pools have tended to draw frowns from eco-campaigners, owing to their strict temperature and humidity requirements but these Max Fordham-designed developments have cut energy demand through a combination of rooflights, advanced ventilation, humidity control and a system which transfers heat from backwash water to the pool. A single heating system includes a ground-source heat pump, solar panels and condensing gas-fired boilers. Rainwater is also recovered from the roofs and used for flushing toilets. Overall, the low carbon technologies here are expected to outperform the Building Regulations by an impressive 35%, at least.

Vulcan House, Sheffield, Mott MacDonald

Vulcan House is set to have a major impact on government offices of the future. The Home Office, which is aiming for carbon neutrality by 2012, plans to use the building's carbon footprint to establish a baseline for the performance of new development projects. Luckily, the designs live up to the role. Sustainable features include insulated ceramic panels, rainwater harvesting systems and a green roof. Parking places are restricted to discourage car use. The figures look good too - the capital cost of the scheme is 5-10% higher than for a conventional office, but reduced operating cost over 15 years will make up for it. And lessons learned from this scheme will be recorded - Sheffield university has launched a three-year study to monitor the energy use of the development as well as staff perception of the building.