Iraq Pavilion, Expo 2020 Dubai

AL SHOLA ALMODEA designed, supplied and installed the lighting for the Iraq Pavilion at Expo 2020 Dubai. The building it had to light is unlike anything else in this portfolio. The pavilion is a timber gridshell, a lattice of slender members curving in two directions at once. It rises and falls across the site, so no two cells are the same shape and no part of it is flat.

Every conventional facade technique assumes a surface. Grazing needs something to graze along; washing needs something to wash. A gridshell has neither. It is mostly air, and what you are lighting is the frame around the holes.

What works instead is lighting the members themselves, so the structure reads as a drawn net against the sky. Because the lattice is open, light passes through it. The pavilion is therefore seen from both sides at once, lit from within on one flank and silhouetted on the other, by the same fittings.

An expo pavilion is a flag before it is a building. The scheme runs the full colour range and holds the national palette when it matters, which is why the shell reads red, white and black on one evening and something else entirely on another.

Colour across a curved lattice is harder than colour across a flat facade, for a reason that only shows at night. On a flat wall every fitting sits the same distance from the viewer, and one setting looks even. On a shell the nearest members are metres closer than the far ones. The same output reads brighter at the near edge, and the eye takes that as a colour shift, not a distance one.

Addressable lighting is normally commissioned by address: fitting one is here, fitting two is next to it, and the controller steps along the row. A gridshell has no rows. The members run in two interlocking directions and the sequence a technician would naturally follow while installing is not the sequence the eye follows while looking.

That means the address list and the position on the shell have to be recorded side by side during installation, node by node, while the access equipment is still under the structure. Reconstructing which address sits where after the fact means either a very long night with two radios or a scaffold going back up.

Programme is the other thing that governs an expo job. Site-wide access is controlled, working windows are shared with every other trade on the plot, and the opening date does not move. Anything requiring a return visit after handover effectively cannot happen, so commissioning has to be finished before the surrounding hoarding comes down, not after.

Public access changes the detail specification too. A pavilion is walked under, leant on and photographed by tens of thousands of people a day. Fixings at low level are specified tamper resistant, and cable runs inside the members, not clipped to their faces.