The Scoop, Union Street

The building “attacked by an ice cream scoop”

That was the Guardian’s verdict on the curve Corstorphine & Wright cut into Union Street. The concave sweep of white glazed brick was designed to frame the round window of the Grade II listed Most Precious Blood church next door, giving its neighbour the limelight rather than competing with it.

Behind the scoop is a careful refurbishment. The Victorian steel-frame and brick building, once home to the London School of Contemporary Music, kept its original street frontage and gained a new extension, becoming five storeys of offices with a roof terrace.

We Design For were the M&E and sustainability engineers, from early design in 2018 through construction, handover and aftercare.

An old building that runs on electricity alone…

The gas supply was removed. Everything now runs on electricity:

• Heating and cooling: heat-recovery VRF heat pumps serve each room individually. Because they can heat one room while cooling the next, heat taken out of a sunny office is reused in a cooler one.
• Fresh air: two rooftop heat-recovery units with 90% heat recovery efficiency supply filtered air, including a carbon filter against traffic pollution on a busy street. CO₂ sensors on each floor adjust the volume to the number of people in.
• Lighting: LED throughout, with occupancy and daylight control.
• Hot water: generated instantly at the point of use, so none is stored and kept hot all day.
• Water: metered, with each WC area shutting off its own supply when nobody is using it.
• Fabric: walls, windows and floors were upgraded where the building allowed. Together with the services, that roughly halved the modelled carbon emissions compared with the building as it was. The design-stage EPC predicted Band B.

Measured, not modelled…

We tested the building rather than trusting the model:

• Indoor air quality: after completion, measured at eight locations. TVOCs peaked at 42 µg/m³ against the BREEAM limit of 300, and formaldehyde at 25 µg/m³ against 100.
• Airtightness: tested at 6.81 m³/(h·m²) at 50 Pa, better than the 10 assumed in the energy model.
• Thermographic survey of the upgraded fabric.
• Aftercare: for three years, energy and water are metered floor by floor and compared against the design predictions, alongside occupant comfort surveys.

The refurbishment is targeted BREEAM Excellent under BREEAM UK Refurbishment and Fit-out 2014.

As featured in: The Guardian · ArchitectureLab · Colossal · gooood

Refurbishing an older building? Talk to us about taking it all-electric.