One of the most challenging things when I was designing The Bunker was where to put the boiler. They take up a huge amount of space when you only have 30sqm to play with.

In the photo, the boiler is hidden in a "cupboard" (top/right) in the bathroom. When you open the door to the boiler there are custom made shelves that wrap around the contour of the boiler, so as to utilise some of the lost space of putting a round object in a square box. This can be used as a medicine cabinet and general bathroom storage.

It would be great to use an instant electric water heater which take far less space, but unfortunately, the electricity needed and the costs involved in France were just not feasible.

I would be really interested to see how others have tackled this issue.