The Aecom VR team engineering the 2018 Serpentine Pavilion

VR visualisation of the 2018 Serpentine Pavilion design.

Seeing is believing with virtual reality (VR). Wearing the HTC Vive headset which Aecom’s design team is using for the 2018 Serpentine Pavilion, it feels almost literally like stepping into the lattice-walled structure designed by Mexican architect Frida Escobedo (see box).

The lighting has been set to 11am on a summer’s day, the sunlight is bright with sharp shadows on the roof tiles which make up the pavilion walls and wind blows the leaves in the treetops. Inside, the mirrored ceiling is starting to take shape and the reflection off the pool is shimmering. The effect is astonishingly realistic.

Carlos Lopes, Aecom’s VR manager, is not yet satisfied though. “I need to add birdsong – VR can feel a lonely place,” he says.

Aecom, now in its sixth year delivering the engineering design for the project in London’s Hyde Park, started work in December.

Principal engineer Michael Orr is working on his fourth Pavilion. “VR is used to get a sense of how the space would feel, which would be hard to communicate with 2D plans,” he says. “It is time-consuming getting to the VR stage but we are getting faster each year.

The HTC Vive headset

“The process starts using the Rhino 3D modelling application – architects like using that as a blank canvas – and we use the Grasshopper plugin to parametrically design the structure,” Orr explains.

“We then take the Rhino/Grasshopper model, and move it into 3DS Max – a graphics program typically used for gaming – to build up the VR model,” adds Lopes.

The lattice tiles sit on a 3m-high steel frame and the tile pattern has dictated engineering and loading requirements, Orr says.

A HoloLens augmented reality (AR) headset demonstrates the steelwork structure. In the AR environment – where your physical surroundings can be seen – the pavilion structure resembles a jailhouse, with two rows of thin vertical bars, and wall-width solid steel members in between, marking the join between the 1m by 1m modules which make up the frame. These are being fabricated off site, with tiles attached, by contractor Stage One.

The tiles – 10,000 in total – each have four holes, to slot over the steel frame. They are supported with a “sleeving system” which fits over the bars in the frame. “Every tile sits on a steel tube and washer, meaning each tile is independent and if one comes out the whole thing won’t come crashing down,” Orr explains.

“One concern about the frame was people leaning against it,” he says. “So we tested it inhouse using the 3D model, then validated that with a full-scale factory mockup, which included giving it a good shake.”

The roof canopy is supported by structural supports, concealed inside three walls – 3m, 4m and 5m long – which define the boundaries of the space.  

“At night, a strip of LED will wash the walls with light, while spotlights are dotted around the ceiling,” says Lopes. “The night visualisations in VR will be fascinating.”

The pavilion opens on 15 June.

Exterior visualisation.

Interior visualisation, showing view towards Serpentine Gallery.

Interior visualisation, showing mirrored ceiling.

This year’s Serpentine Pavilion is influenced by architect Frida Escobedo’s Mexican homeland.

It sits on a 20m by 12.5m rectangular footprint defined by freestanding cantilever walls with two entrances. The inside of this courtyard is partially covered by a curved roof canopy, a trapezoid on plan, 17.5m at its longest point and 10.75m at its widest, and set at an angle to align with Prime Meridian in Greenwich. The courtyard also features a pool of water outside the covered space.

Both internal and external walls use tiles stacked on a steel framed structure to create a lattice effect, otherwise known as a “celosia” – a traditional breeze wall common to Mexican architecture. The intended effect is of sharp contrast between areas of dark shadow and bright light – and how they change during the day.