If this sounds profoundly stupid to you, well, you're not alone: no other major American city imposed such a requirement, and actual fire safety experts universally agreed that landing a helicopter on a *burning building* is incredibly unsafe. dailynews.com/2014/09/29/los…

And yet, for 40 years, the rule persisted. Besides the non-negligible added cost of adding a helicopter landing pad, the rule also meant that an entire generation of Los Angeles high-rises had to be flat topped. No spites, no ornamentation.

There was only one documented use of a helipad for fire abatement in their 40 year history: the 1988 First Interstate Tower fire—a building that burned because, while it had a helipad, it didn't have sprinklers. Odd priorities! latimes.com/opinion/op-ed/la…

Though the mandate had long been known to be silly, it took until 2006 for Mayor Villaraigosa to propose its repeal. Without data, but with one visceral (if easily resolved) example, LAFD delayed repeal until 2014. Thus, another eight years of helipad-clad high-rises.

If this sounds unusual, it isn't—cities often impose dubious requirements on the basis of fire safety that have hidden costs. Mandates that residential streets be wide enough for a large fire truck to barrel down them more often than not just encourage deadly speeding.

Likewise, a growing chorus of North American practitioners are challenging egress requirements that are out of step and make infill housing infeasible—and bumping into a hard "no" from fire officials before the issue has even been studied. secondegress.ca/

Fire safety is important—so important, in fact, that it should be rooted in evidence, not vibes. /🧵