The new Maggie’s cancer care centre in Leeds proved its worth as a still, small place of calm and contemplation even before its pandemic-delayed official opening in June.
The all-timber building, designed by Heatherwick Studio, is on the St James Hospital site in Leeds, its fluid organic curves contrasting with the towering blocks of the Bexley Wing, Europe’s biggest hospital oncology research centre. As it couldn’t receive its first visitors at the height of the health crisis, due to their vulnerability to infection, it was offered instead as a tranquil oasis to hospital staff.
“When the hospital was busiest coping with Covid-19, it became their refuge,” said Nick Ling, Heatherwick Studio technical design lead. “It was a space of respite from the stress of the clinical environment.”
Heatherwick had worked on healthcare projects before. It provided input for new clinical facilities at Great Ormond Street and developed design guidelines for centres being set up by One Small Thing, a charity which supports ex-offenders as they reintegrate, including providing health services.
But Maggie’s Leeds was the design and architecture studio’s first standalone facility in the sector. It was, said Mr Ling, a demanding, sometimes humbling experience.
“In all our construction projects we try to unpick the brief and find a way for the building to improve the human experience – but Maggie’s posed challenges we hadn’t encountered,” said Mr Ling. “The charity’s founder Maggie Keswick Jencks went through her own cancer journey and had to process her diagnosis in a windowless hospital corridor. She thought there must be a better way and the Maggie’s Centres concept was born. We had to understand and get beneath their ethos.”
Initially the studio thought there might be a “magic bullet” design form that could meet Maggie’s requirements – “a bit of exposed timber, some plants”.
“But through the back and forth on our designs, we realised it wasn’t that easy,” said Mr Ling. “They took us through the psychological implications of our ideas, to let us see them through the eyes of centre visitors. It was about understanding connotations of design for people going through this experience, both visual and spatial. Somewhere that looks pretentious or too pristine isn’t a comfortable place to be. Maggie’s explained that the building mustn’t feel institutional in anyway. It had to be a space that puts people at their ease; somewhere they can really talk about what’s going through their minds and staff can help them process that.”
The Heatherwick design team looked at various materials palettes and building formats. But timber-based construction best suited the project for a range of reasons.
“Deciding on all timber was a breakthrough moment – it solved problems without creating new ones,” said Mr Ling. “There’s the increasingly understood wellness properties of wood, and its biophilic benefits. It’s tactile and creates a homely feel. Maggie’s was easily won over too. They love natural materials and other recently built centres are timber-based.”
Wood also worked due to its relative lightness. The small, steeply sloping site had been used to dump construction waste and subsequently turfed over.
“We didn’t want to spend a chunk of the budget on clearing the rubble and putting in deep piles down to the bedrock,” said Mr Ling. “Using lightweight timber allowed us to use a relatively shallow raft foundation.” Timber also won out through its suitability for prefabrication.
“The ambulance blue route runs around the site, so we couldn’t have road closures. We needed minimal deliveries and prefabricated elements we could quickly crane off the truck and drop into place,” said Mr Ling.
The Swiss timber building fabricator Blumer-Lehmann, which supplied all the engineered wood elements, in fact, managed to package everything into three main deliveries. That’s one for each of the mushroom-shaped ‘pots’, as Heatherwick Studio calls the centre’s three interlinked core structures.
Blumer-Lehmann was chosen for the job because of its track record on projects that were just that bit out of the ordinary, or technically challenging. Heatherwick also liked its environmental story.
“UK fabricators we looked at sourced their engineered timber from Europe, then processed it here,” said Mr Ling. “Blumer- Lehmann sources most of its engineered wood in Switzerland, then supplies the elements ready to install, so no excess or waste timber is transported. Also Swiss mills that supply them use 80% Swiss timber so it doesn’t travel great distances. Blumer-Lehmann finds a use for all its offcuts too. We just liked the neat circular life of its timber.”
The project partners liaised on the design and engineering process remotely.
“We fine-tuned 3D models online; we’d address the aesthetic geometries, then they’d do the engineering,” said Mr Ling. “It turned out to be an effective, efficient process. Blumer-Lehmann made everything to millimetre precision and it clicked together like a kit of parts.”
At the heart of each pot is a round cornered rectangular core comprising stressed diaphragm timber and plywood cassettes. These resist the lateral loads and in the finished building are used to house consultation and other rooms and services.
On to them are fixed spruce glulam fins in a range of dimensions, depending on the structural properties needed. These provide cantilevered support for the pots’ CLT roof slabs, which, in turn, support an ‘intensively grown’ roof garden.
“Part of our concept was to create a building that sat beneath a garden,” said Mr Ling. “While the site previously was just a bit of grass and a few trees, it was the hospital’s only green area and cherished. We wanted the centre to be a calming, natural place to be in, but also to look down on from the hospital.”
The weight of the garden meant the cantilever fins needed additional support with columns and beams. Steel was considered for the job, but Blumer-Lehmann wanted to “optimise the solution” and avoid the complexity of steel/timber connections.
So it recommended LVL, specifically beech BauBuche from Germany’s Pollmeier. “It’s supposedly an industrial grade product, but we fell for it!” said Mr Ling. “It’s hard and strong, and we’ve used it as well to reinforce stress points in other parts of the building, but when you machine it you also see the grains of the different veneers, creating a beautiful effect. We liked it so much, we also used it for window cills, stairs and trim between stairs and the cementitious epoxy resin flooring. We designed a couple of tables for the centre too, with cork tops and legs shaped to mirror the building fins, but in LVL.”
The falls on the roof comprise plywood boxes, filled with wood waste from processing the timber elements for added insulation.
“And we’ve used a self-healing bituminous coating on top,” said Mr Ling. “It never properly sets, so if it’s damaged by an over enthusiastic roof gardener, it reseals.”
The building is proving to be thermally efficient. It has an electric underfloor heating system and energy efficient windows and glazed walls, and the timber is also an inherent insulant.
“The precision of the components resulted in it easily passing air leakage and cold bridging tests too. In fact it exceeded Part L targets by 12%,” said Mr Ling. “And the fact that the structure is partially sunk into the ground further adds to its thermal properties.”
Lime plaster is used on some walls internally for its porous qualities, to help maintain humidity in the naturally ventilated structure. But the timber is allowed to shine through inside and out.
“We’ve used a surface spread of flame treatment, but that’s clear,” said Mr Ling. “We were concerned that the fins, which are expressed internally and externally, would colour differently, so we also used simple brush-on UV treatment, which gives the wood a translucent white wash. The wood outside is also protected by the roof overhangs and Blumer-Lehmann says it shouldn’t need any other protection – and the frame went up late 2018 and so far shows no significant signs of ageing.”
While the lockdown delayed completion of Maggie’s Leeds until this year, the superstructure was erected by Blumer- Lehmann installers in just three months. Now the building is open and the feedback from Maggie’s is positive. They report visitors relating to the building in different ways.
“People are finding places to sit and reflect, but also engaging with the open social spaces,” said Mr Ling. “The staff also like the fact that there are lines of sight across the interior, but at the same time, the building’s three pots, and the fact that they’re on different levels down the slope, create the feeling of separate areas.”
As for Heatherwick Studio, it has been confirmed in its conviction that timber should be embraced as a mainstream construction material.
“We advocate natural materials and timber in particular wherever possible. For instance, for the new Google building in London’s King’s Cross we’re including CLT floor slabs and Accoya mullions in what will be the UK’s biggest timber curtain wall,” said Mr Ling.
“It’s not just a key solution to minimising construction’s carbon footprint and helping tackle the climate emergency, it lends buildings a real human connection.”
