Green giant

Since Rab Bennetts and his wife Denise set up Bennetts Associates in 1987, the architectural practice has built a reputation for pioneering new ways of thinking in the commercial sector. Two of their most influential buildings, PowerGen’s headquarters in Coventry and Wessex Water’s operations centre on the outskirts of Bath, broke new ground in terms of energy efficiency and office layout. The latest building to emerge from the firm’s Clerkenwell offices, though, is aimed squarely at the public. “The most important thing to influence the design of the Jubilee Library in Brighton was that it should feel like a proper public library,” says Rab Bennetts. “We felt it should be an imposing civic building with real presence.”

Sustainable design and low energy usage have long influenced the practice’s work and the Brighton scheme is no different. But Bennetts is by no means dogmatic in his approach. While the Jubilee Library makes the most of its shape and form to create a simple, low-tech servicing solution, for large parts of the year it will be mechanically ventilated. “The fact that it is not purely naturally ventilated is something I am happy with,” he says. “We’ve found with a number of projects it can be a better option overall than natural ventilation.”

For Bennetts, architecture and services have always gone hand in hand. He says: “You can never design a building without complete integration between the space, the structure and the environmental engineering.” When this approach is combined with a knowledgeable client, the result is usually better than the sum of the parts. This was the case with the building for Wessex Water. Yet getting it to perform, as intended was far from easy – it took two years of post-handover fine-tuning to get it to work in accordance with the original design. “Now that is quite significant – you could gain 10% to 20% improvements in energy efficiency just by fine-tuning and I don’t think that is generally realised,” says Bennetts.

He believes that the lack of post-occupancy feedback and hard data on how buildings perform is a barrier to real sustainable design. “Hardly anyone routinely follows up post occupancy evaluation and I think there should be some kind of system to make them do that,” he says. Currently he is trying to encourage the British Council for Offices to survey all the buildings it presents with awards to find out if they live up to their design aspirations. “You get architects and others standing up and saying they have designed a green building and nobody is ever able to challenge that.”

From an architectural perspective, 2002’s changes to Part L didn’t have the radical impact on buildings design that Bennetts thought they might. “It certainly didn’t change the way our buildings looked but it has at least made people think about glassy transparent buildings, which are an obsession with modern architects.” The 2006 update though could finally spell the end for such designs, or at least calm down the high-tech responses such as triple-glazed facades, that Bennetts says defy common sense. “I think people are finding they are right at the limit of what you can do with transparency; maybe we will finally admit that it might be best if we just have less glass.”

Over the past two years the practice has also become involved in masterplanning, notably for the City Road Basin mixed-use development in north London. Incorporating CHP plant for the main blocks and aiming for Excellent ratings under BRE’s EcoHomes scheme, the plans have been well received by the Greater London Authority under its London Plan. The scheme will provide about 900 inhabitable rooms a hectare and it is this increase in building density that Bennetts says will be the biggest factor in changing the face of the capital in the long term. “The London Plan will have a bigger impact than, say, the proposals put forward in the Olympic bid because of this potential to increase capacity. Contrast that with what we would have done before and it makes a huge difference in how you design.”

If Bennetts does have reservations, it is with the mayor’s energy strategy, which he argues would be better allied to maximum energy consumption targets for buildings, instead of goals for how much energy should be delivered by renewables. “There is a bit of tokenism about this renewables strategy, which is not ambitious enough. Why don’t you set everyone a target to reduce energy consumption by 50% against known benchmarks, and then think about renewables – that way you can make bigger changes.”

Islington council has now approved the City Road Basin development and the first of the high-rise towers has been granted planning. The initial buildings won’t be finished until 2008 but if previous projects are anything to go by the results should be worth the wait.