Few horizontal application sectors of ICT have proved as elusive and illusionary as smart buildings, a concept that first did the conference rounds almost four decades ago in the early 1980s. Each generation of course is circumscribed by the technology available at the time, but at all stages progress seems to have been stymied by lack of integration, as promising islands of automation fail to be joined up properly. That seems still to be the case today, or at least very recently, if we judge by how Google’s smart buildings strategy slid into disarray despite, or even because of, the success of Nest, the smart thermostat company it acquired for $3.2bn in January 2014. Nest established a highly successful island…