Britain’s ‘greenest’ building - reed all about it

What’s billed as Britain’s “greenest” building yet is creating quite a stir at the University of East Anglia (UEA), not least because it brazenly shows off its credentials with facades clad in vertical reed and straw thatch; it’s got to be the architectural equivalent of the hula hula skirt.

The university’s new Enterprise Centre, now under construction, is the first building that visitors see when they enter its Belfield-style campus at the edge of Norwich, and it was designed to make a major statement about UEA’s commitment to the sustainability agenda.

Although some might see the use of thatch as a shameless gimmick, architect James Todd defended its selection on the basis that the reed and straw were traditional building materials available locally, and that using them for cladding also "captures the whole spirit of the project".

Todd, an associate in Architype architects specialising in low-carbon design, describes the thatched façades as "completely innovative and unique". For centuries thatch was used for roofs, although it has been hung vertically lately on a couple of new buildings in the Netherlands.

At UEA the thatch went through three or four prototypes before the architects decided to use straw panels for less exposed parts of the three-storey building and reed for areas more challenged by weathering.

It will all turn silvery grey over time, Todd says.

The predicted life of the thatch is an optimistic 60 years, with the straw likely to require replacement earlier than the reed.

Junctions between the panels, which were visible during our visit, are to be combed out by specialist thatchers to ensure a smooth finish.

A pair of “light scoops” on the flat roof are pitched at an angle of 45 degrees (to capture as much daylight as possible and draw it into the building). It was a mistake to thatch these elements as they detract from the building’s unique selling point; slate would have been better.

There are solar panels on the otherwise flat roof, which is being ringed by an aluminium-clad parapet. The hanging thatch below it will also be trimmed over the windows and generally given a good “haircut” so that it ends up looking exactly like the photomontages.

A timber-framed structure (the only concrete in the building was used for its foundation slab), it was built using Corsican pine harvested from Thetford forest – but with all of the sawn timber sent to Macroom, Co Cork, where it was turned into construction material by Cygnum.

The firm, now nearly 20 years old, had the foresight to set up an office in Suffolk to scout for work in Britain after the Irish construction industry began to implode in 2007. Its big breakthrough came with a new school in Wolverhampton, built to “passive house” standard.

Architype were also the architects on that project, as managing director John Desmond recalled.

And the primary school principal was so pleased with the comfort it delivered that he wrote a letter noting that the children were “much more alert in the afternoon” as a result.

Working with Architype as a specialist subcontractor Cygnum supplied bespoke timber frames for several other schools on the strength of its first in Wolverhampton before winning the tender to build UEA's Enterprise Centre with Architype and main contractors Morgan Sindall.

Desmond describes it as a “pretty extraordinary project” to work on. Cygnum’s in-house design process for the timber frame took six months, then each part was made, numbered and bundled together for transport to Norwich, where it was assembled by a specialist crew.

John French, CEO of UEA's Adapt Low Carbon Group – client for the £17.5 million (€23.6m) project – says he is "thrilled to bits" with it.

The group has invested £60 million (€81m) so far in low-carbon enterprises in what he calls an exercise in “left-of-centre capitalism”.

French expects that the new Enterprise Centre will enrich the architectural legacy of UEA, which includes Denys Lasdun’s ziggurrat student housing and Norman Foster’s Sainsbury Centre for Visual Arts, both energy guzzlers from the 1970s and now protected structures.

James Todd thinks that the naturally ventilated building will even become a “carbon sink”, soaking up more than it produces.

John Desmond wonders whether Irish universities and the Department of Education will “sit up and take notice” of what’s happening at UEA.