In December 2002, as Norman Bragg, principal director of Arts Team, stood on the brow of a hill and looked over the bare winter landscape of the Chilterns, he knew he had a metaphor for Aylesbury's new civic theatre.

Arts Team, part of RHWL Architects, had just joined Crest Nicholson in a bid for the regeneration of Aylesbury town centre, and Bragg was making the journey from his home in Hertfordshire to the site in Buckinghamshire for the first time. He decided to turn off the A41 and explore the hills that lie between the two counties. He was not familiar with the area but as he stepped out of the car and saw the roll of the hills and the forest, he was inspired. “It's absolutely stunning,” he said. “On the way back, in my mind I developed the form that the building was going to take: the undulating lie of the Chiltern hills, mixing that with the strong vertical pine trees. It was an easy metaphor to take because it was so stunning.”

The team went on to win the bid, and the design for the £25m project, which replaces the rather tired, 1970s venue on another site, will be submitted for planning permission next month.

And the quick sketch that Bragg did when he arrived home from that initial journey has formed the basis for the new theatre. The undulations of the Chiltern hills will be reflected in the lines of the slate plinth and the metal roof, while externally and internally, the use of timber will provide the layering of textures and depths of the forest.

A stainless steel flitch plate will connect the external fins to the high level roof timbers

“When you look at the building from a distance there will be a different perspective from when you look at it close up,” said Bragg. “As you go nearer you start to see beyond, into the building. It's layering. As you look through a wood you don't just see a wall of trees, it goes into its depth.”

This layering will be particularly evident at night when the interior lighting will throw shadows across the façade.

The amorphous building will be supported by around 150 exposed laminated timber “fins”, rising 10-15m and spaced irregularly around the exterior. With one flat edge and another on a large radius they will appear to lean out from the glass face and will be “stitched together” by timber transoms, also placed at irregular intervals. On the façade the input by structural engineers Whitby Bird has been particularly welcome.

“The trees in the forest are not set out in regular lines so we've taken this irregular pattern,” said Bragg. “The fins are deliberately set at different centres to give an echo of the random approach that you get in the forest.”

The vertical structures will probably be made from PEFC-certified European larch or North American Douglas fir – chosen for its durability – and, while the timber could be left to weather naturally, for this project Bragg's choice is to use a light pigmentation to maintain the warm colour of the species. Ideally it will be applied in the factory and provide a six- to eight-year maintenance cycle.

“For a building of this sort of civic nature and this very prominent site in Aylesbury, I would prefer to find some solution that can maintain that wonderful colour that you get from the material,” he said.

The structural timber “fins”, rising 10-15m, will be made from laminated European larch or Douglas fir

A decision has yet to be made on the transoms but, reflecting the diversity of a forest, a different species will be used. “We don't have a problem with the size or scale so we have much more freedom,” said Bragg. “I think they need to be different in colour and feel but we'll probably do more testing. They should read as a horizontal timber member but as a slightly different family, so it isn't one tone across the whole façade.”

While the logistics of transporting the large timber fins will be worked out in the procurement process, Bragg is adamant that timber is the right choice. “It's a wonderful material because it's so pliable,” he said. “If we were talking about these being in say, metal, if you get any damage then they're ruined. Timber is such a marvellous material: if you get a problem you can repair it easily. I haven't chosen it primarily for that reason, I've chosen it because of the inspiration from the Chiltern hills, but nevertheless I'm absolutely convinced that it's the right solution.” á

Ü At the heart of the building is the main auditorium. When Bragg was working out how to link this “heavy, solid centre section” with the façade, he thought back to his initial journey through the Chilterns, hence the foyer will create another image of the forest.

Although the interior design is still being developed, conceptually it is complete – and timber stars again. “I don't want to build this out of concrete and then clad it in timber; I want to try and do it all in timber,” said Bragg. Here timber columns – again, possibly in larch, although with a different feel from the external structures – will support timber decks, with timber balustrades, and a timber ceiling. Bragg is particularly pleased with the latter which again uses the layering approach to create depth.

CGI showing roof elements and timber fins supporting the façade and roof
construction

Using timber also helps Bragg achieve his aim of creating a building with enough nooks and crannies for theatre-goers to discover something new on each visit. He wants to create a building that has “great interest, and many new areas so that one can explore, almost like a young child, and each time they go back to the building find new areas that they haven't discovered”, he said.

In the auditorium, which has a 1,200 seat capacity, with 1,800 standing, Bragg is working on the idea of using “stacked timber, like timber in a yard”, but in a more random fashion. “If we can bring that round into the walls, I think we can create a fascinating new auditorium,” he said.

“Timber is a wonderful material for the auditorium,” he added, “because it's warm and it's good to touch.”

Bragg has yet to address the venue's function suite – a simple, rectilinear space with a capacity for 240 “in many different configurations”, but said he would be “rather brave” if the design did not include timber. “We have such a strong image of this forest of timber as you go into the building; I'd feel rather sad if I couldn't complete the whole building on it.”

Work is due to start on site next May and the project is expected to take two years. When it is complete, the town will have a landmark building, and a modern theatre, on a prominent site. Bragg is clearly excited about the project and he applauds the vision shown by Aylesbury Vale District Council.

“This is a significant undertaking for them to be building a theatre of this quality. For them to be able to pull the wherewithal together to do that is a remarkable achievement for them,” he said.

But while the council may appreciate the need for a new theatre, what will the theatre-goers make of it?

“The building is for the people of Aylesbury. The pleasure for me will be if they enjoy the building and the experience. If they pick up on the journey then that's marvellous, but if they just enjoy themselves and see that there are many exciting places in the building that they can visit then, to me, that will be a success.”