Given that the value of a high-end collectible car—from a classic to a supercar—can easily exceed the average sale price of an Old Master painting, it’s surprising how many of these dream machines are still stored in insecure, climatically unsuitable places: domestic garages, old agricultural buildings, and even public car parks. British start-up Birch aims to change that.
Its founders are serious car collectors who struggled to find suitable accommodation for their…

