Cladding – wasteful, too complicated and prone to failure?

Steve RIBA J

A simpler approach to construction, using fewer materials and layers that work together, would create buildings that are less complex, says Steve Webb

Recently, I was sitting in a coffee shop idly watching some construction workers cladding a kiosk. I was egg-shaped.

Between the sections of pressed metal cladding sheets I could see metal rails and glass-fibre insulation, some cold-formed studs with cement board pinned to the back, bits of secondary support steel and then a big bolted connection of primary steels. I imagined inside were more rails, more insulation and plasterboard.

An eggshell is made of calcium carbonate – chalk – about 0.3mm thick. Schoolchildren are taught that eggs have a great structural shape. They are not indestructible, but are extremely strong in comparison to their material use. They are permeable to water and air and form a mitigating layer between internal and external conditions.

I am not always convinced by biomimicry. Our understanding of what we are mimicking can be glib or oversimplified, but in this case, a building the shape of an egg has to be an open goal.

I can only imagine that the multiplicity of layers being used on the kiosk arises from dividing the shell into seven different tasks, dividing those tasks between seven different subcontractors and telling each of them to make their part cheaper with no regard to the whole.

How can we make buildings more succinct? We need materials that provide structure, insulation, waterproofing, durability and have a suitable aesthetic quality.

What are these materials? It’s not easy to solve so many problems with a single deft move. CSK’s cork house was a brave attempt. Cork inside, outside structure waterproofing and an olfactory pleasure to boot.

Baumschlager Eberle’s 22/26 is also noteworthy. Just bricks, no insulation, no membranes. But let’s not forget bricks are bad because they’re made using coal. I asked UK Hempcrete if its product could be left unsealed both externally and internally. Taking Practice Architecture’s Flat House as an inspiration, I think a Hempcrete wall exposed in and out would be a nice thing. They weren’t recommending it, but hadn’t really tried.

Going back to the egg, all the layers are wasteful of material, overly complex, prone to failure and, above all, an offence against reason.

Putting the design of buildings in fewer people’s hands, teaching designers and contractors to value the succinct and question the addition of complexity while investigating in the development of good materials that work for several disciplines, not just one, would be a good start.

This article was originally published on RIBA Journal.