The latest in the AJ’s retrofit case study series looking at architects who have saved buildings from the bulldozers or given them a brand new life
RetroFirst Logos 2019 3
With up to 40 per cent of carbon emissions coming from the construction industry, the profession needs to find ways of adapting the type of buildings it designs, and fast.
In order to tackle the climate crisis, the default – and less carbon-hungry – option for any project should be to adapt and reuse an existing building, one of the key demands of the AJ’s RetroFirst campaign.
With the spotlight on retrofit, our ongoing series seeks to celebrate the projects that save buildings from ruin or resurrect them in innovative new ways and to hear from the architects that designed them.
Today we hear from Morris+Company director David Storring about how the practice is using timber – and overcoming major challenges with dry rot – to create a new enterprise hub for Goldsmiths University within and behind a four-storey Victorian parade of shops.
Tell us about the project?
We bid for this project in June 2019 as part of the ADUP framework, which we are on. The project goes to the heart of what we do – a community-based project with a wide variety of uses connecting many different types of people to education in its many forms.
Since winning it, we have been working closely with Goldsmiths, University of London, Greater London Authority, Lewisham Council, local businesses and the community to develop a vision for a largely disused Victorian parade of shops in New Cross Road. It will provide a new creative workspace, café, garden and community space.
David Storring, director, Morris+Company
I live in New Cross. It’s on my doorstep and I was really keen to see this terrace being brought back to life.
The Goldsmiths Enterprise Hub will provide a 1,494m² sustainable creative business ecosystem, comprising incubation and innovation space for enterprise, support, networking and knowledge exchange for local entrepreneurs, small businesses, students and alumni.
The scheme will not only add to the existing university campus, it will also benefit the New Cross community at large. Recently approved by Lewisham Council, work is due to start on site this year, with the Hub opening in 2021.
One of the key interventions is a new chamfered entrance to the corner of the terrace shop front to draw people in. This signifies the main public route into the Hub, activating the neglected laneway and framing the new accessible link to the former Deptford Town Hall, a currently underused Goldsmiths building. New openings in the terraced party wall will link the ground floor to provide a flexible exhibition, event space and café, creating opportunities to showcase emerging talent.
We have extended and ‘repaired’ the rear of the terrace with simple brick detailing, clay tiles, precast coping elements and expressed downpipes, referencing the existing condition, but reinterpreting it in a contemporary way.
The second floor set-back roof profile breaks up the massing to create a playful repeated form. This contrasts with the ‘new’ timber pavilion and Deptford Town Hall linking elements, which are expressed externally as filigree metal façades looking onto the new garden, referencing the decorative metalwork that adorns Deptford Town Hall.
Exploded isometric section (with building overlay)
What were the challenges of the existing buildings?
One of the biggest at the design stage was tying together the floor levels across the numerous buildings, to create a fully accessible scheme, while minimising the changes to the existing buildings.
One of the biggest challenges was tying together the floor levels across the buildings
The terrace is on a sloping site, so connections through the party wall required careful placement of ramps integrated into the design to deal with the change in level. Even more difficult, was tying the levels of the staircase into Deptford Town Hall’s grand ceiling heights, which were very misaligned.
We developed numerous design solutions and settled on a through lift and bespoke timber stair, which ended up taking on a sculptural form as it snakes between the various levels.
Had demolition or partial demolition ever been considered?
The existing building sits within the Deptford Town Hall Conservation area and plays an important role in the setting of the Grade II-listed town hall, so demolition of the buildings was never a consideration.
Existing rear facade of terraces
However, there was a lot of discussion about the partial demolition and rebuilding of the rear of the terrace. After working through numerous iterations we realised the only way to provide accessible access and to connect to the Town Hall, while also providing the types of spaces that the Hub needed, was to demolish the rear brick wall.
To minimise the impact of this demolition, we are reusing the bricks to form the retaining wall to the planter in the courtyard, ensuring we put them to good reuse.
Aside from retaining the original fabric, what other aspects of your design reduce the whole-life carbon impact of the building?
From the outset we were keen that all new intervention would be as low-carbon as possible. This was reflected in Goldsmiths’ brief. They are currently conducting carbon analysis throughout their estate and have identified that the majority of their landfill comes from construction on-campus.
The majority of Goldsmith’s landfill comes from construction on-campus
This approach informed the early design decision to construct all newbuild structural and linings from sustainably sourced timber fabricated offsite, bringing a natural softness to the spaces whilst sequestering CO2, at the same time eliminating waste.
We worked closely with Skelly & Couch to bring the services as close to carbon neutral as is feasible with an existing building. All of the new-build elements, including the pavilion and link are naturally ventilated via the tall volume of the link, staircase, and circular lantern, creating a stack effect to cool these spaces. We also made sure energy efficient air source heat pumps were used in the terrace to mitigate noise from the busy high street.
What have been the main lessons from the project that you could apply on other developments?
The importance of having experts on the team at an early stage. The terrace had suffered from significant dry rot, which posed a considerable challenge in balancing the preservation of the building fabric while trying to increase the environmental performance of the building.
Fortunately, there was a dry rot expert involved at the very start, who helped us tackle this right away. In the end we chose to leave the brickwork exposed throughout the terrace, allowing the walls to fully dry out and breathe, while also revealing the hidden history of the terrace’s construction. We avoided adding any insulation to the external wall as the risk of increasing the dry rot was deemed to be too high. What is the point of an energy efficient building if it has to be pulled down in a few years?
What skills do you need as an architect on a retrofit job?
Retrofit projects come with a wide range of challenges and it is important the architect has a broad set of skills, from restoration and knowledge of historic building methods, to new construction techniques and how these two very different methods join.
Being flexible and engaging with the contractor on site is also very important, particularly when the realities of the historic building fabric do not match the millimetre-perfect CAD in the office.
Large timber scale model of pavilion and link to Deptford Town Hall
Source: Morris + Company