Learning From Experience

The reports are coming out about the investigation of the Grenfell fire and, unsurprisingly, the facts are awful. A building fire that killed 72 people is going to involve massive failures of design and construction, and that’s exactly what we’re seeing. The flammability of the exterior over-cladding* has been fairly well documented at this point; the other design and maintenance flaws, including improper fire-stopping and under-rated** doors, are less spectacular than the over-cladding failures but just as damning.

It cannot be stated often enough that engineering developments are in large part triggered by failures. Structural design has moved ahead for centuries based on avoiding known failures; to this day, failures are studied in order to improve our design methods***. Similarly, fire prevention and fire-resistance of buildings has been advanced by the study of major fires, including some which are quite famous. The  aftermath of the Triangle and Cocoanut Grove fires improved egress; the aftermath of the Meridian Plaza and the MGM Grand fires improved sprinkler use.

The problem of exterior fire spread has been known for centuries, and the high-rise version of this problem since the 1890s when several fires in the new generation of tall buildings – early skyscrapers – made it clear that fire could jump from one floor to another through windows. It’s horrible to say that people don’t remember these hard lessons unless they see them happen in their lifetimes, but the recurrence of tragic fires and the repetition of mistakes, such as using an over-cladding material that was more flammable than the standard rating for exterior walls, suggests that is true. To learn from past tragedies we have to remember and understand them. Even a hard-nosed engineering discipline like forensics depends in part on history, record-keeping, and communications.

* Over-cladding is a facade veneer that is fastened over or through an existing veneer. The flammable facade materials at Grenfell were a retrofit intended to improve aesthetics and weather performance.

** In order to maintain the fire-rating of a hallway, every door that opens onto it must be rated as well.

*** And, of course, the codes that standardize design methods.