Architecture

Photo: Dennis Gilbert

Architype’s low-energy Enterprise Centre at Norwich Research Park pairs vernacular materials with Passivhaus principles; words by Max Fordham

The Enterprise Centre at the University of East Anglia’s Norwich Research Park, built by a team including architect Architype and intended to encourage the cooperation of academia and new business, is described as the UK’s greenest commercial building.

Photo: Dennis Gilbert

In terms of sustainability, its distinguishing feature is that it has been constructed in such a way that its embodied energy is virtually negative. Photosynthesis combines water and carbon dioxide using solar energy and releasing oxygen. The process produces plant material, most of which decomposes as fast as it is made and returns the carbon dioxide to the atmosphere. The carbon cycle in nature is in equilibrium until we start to burn carbon fuels. When we fix plant material into a building for 100 years or so, that is an offset for whatever carbon fuel we have burnt elsewhere.

Photo: Dennis Gilbert

Architype’s embodied energy calculations give a figure of 440kg/CO2/sqm across the 100-year life cycle. This equates to a quarter of the lifetime emissions of a conventionally constructed university building of equal size, but I am surprised that it isn’t a negative number. Almost every part of the building is based on timber or cellulose, though there are exceptions; the ground floor was going to be suspended timber until it was replaced by a low-carbon concrete raft for economic reasons. The timber sheathing that replaces plasterboard raises the thermal capacity of the building, and is a favourite material for art gallery walls. Wood wool acoustic boards also offer low embodied energy. The attention to the possibilities inherent in the material shows in every part of the construction detail.

Photo: Dennis Gilbert

The most striking manifestation of design for sustainability, however, is the use of thatch as a rainscreen.

Photo: Dennis Gilbert

The building’s plan-form is of a type well established for use in simple commercial developments: a two-story E-shape with narrow wings so that natural light and ventilation penetrate effectively. The storey heights have been set to suit the lighting strategy, with rooflights for the first floor.

Photo: Dennis Gilbert

The building was designed to achieve a BREEAM Outstanding rating. The systems for scoring sustainability are difficult to credit. Designers work hard to tick the boxes to give a good score, but the scores are based on calculations that are subject to considerable inaccuracy, and it is not surprising that post-occupancy studies of the performance of buildings do not bear out the hopes of designers. The scoring systems are useful checklists, but there is no substitute for making sure that buildings are well commissioned and that the construction is improved during the first years of use.

Photo: Dennis Gilbert

The Passivhaus principles for low-energy building have been in development for several decades, and do meet the well defined aim of minimising the carbon footprint of a building. The Enterprise Centre has been designed to meet these criteria, which lead to a highly airtight building that needs virtually no heating. Its wall area might have been be reduced if the plan was more compactly organised round an atrium, but the Passivhaus standard simply requires that the wall area and level of insulation should be reconciled.

Photo: Dennis Gilbert

Cross-ventilation is simplified by this plan. In winter, the mechanical ventilation with heat recovery (MVHR) system provides fresh air with almost no heat load.

Photo: Dennis Gilbert

Window areas are modest, so triple-glazing is affordable. Being free from over-glazing, the ventilation required to offset solar gain will not be extreme. Even so, management should try to ensure that night ventilation for very hot weather can be provided without a security problem. Natural light is used as much as possible, including via first-floor rooflights, and the combination of background electric lighting with brighter task lighting only where required should impose a low electricity load.

Photo: Dennis Gilbert

For buildings such as this to work as intended, occupants have to be trained and persuaded to use it as well as possible. UEA’s client team is experienced in both commissioning and using buildings, not least through developing the Elizabeth Fry Building (John Miller & Partners with Fulcrum Consulting, 1995), whose lessons were applied to the Enterprise Centre.

Photo: Dennis Gilbert

This building shows how a sustainable office building can be designed to meet Passivhaus standards. The architects have done all they can. But its final sustainability depends on the availability of carbon-free energy to meet the demands of office work. The big question is whether we – a global population heading for 10 billion people – are going to be able to keep our demands for electricity within the generating capacity of wind turbines, hydro-electricity and wave power.
Max Fordham is an engineer, pioneer of sustainable design, founder of building services firm Max Fordham LLP and a past president of the Chartered Institution of Building Services Engineers.

Project team
Architect: Architype; project team: Ben Humphries, James Todd, Gareth Selby, Christian Dimbleby, Mark Martines, Rosie Evered, Tom Wall; contractor: Morgan Sindall; landscape: Churchman Landscape Architects; M&E, structural and acoustic engineer: BDP; lifecycle cost analysis: BSRIA; client: University of East Anglia and The Adapt Low Carbon Group
Selected suppliers & subcontractors
Glulam frame: Kaufmann, Inwood; timber frame: Cygnum; OSB3 boards: Smartply; slab insulation: Isoquick; insulation: Warmcell, Diffutherm; air tightness tape: SIGA; roof and wall sheathing: Timbervent by Egger, Sarket by Hunton; plywood: WISA; thatch: Stephen Letch; MDF cladding: Medite Tricoya; lime render: Baumit; wool wood acoustic boards: Troldtekt; cellulose acoustic finish: Sonaspray; truck tyre flooring: Jaymart Flex-tuft; paints and oil finishes: NBT, Osmo; linoleum: Forbo Marmoleum; LED lighting: Fagerhult