The wash-up area hits 40°C by midday. Condensation drips from the ceiling onto clean plates. The walls are wet. Staff are drenched in sweat and can barely stand to work back there for more than twenty minutes at a stretch. If this sounds familiar, you’ve got a ventilation problem — and it’s one of the...

A head chef at a busy Indian restaurant in Brick Lane called us mid-service. Smoke from the tandoor was filling the kitchen instead of being pulled up through the canopy. Front-of-house staff were propping open the fire escape to clear the haze. Customers could smell it in the dining room. The extract system had been...