In Finland the building code requires that all office spaces and apartments have a window. It's possible to circumvent this by putting an office into space tha

In Finland the building code requires that all office spaces and apartments have a window. It's possible to circumvent this by putting an office into space that was designed as storage or as factory. But you will then usually also lack toilets, kitchen and decent air condition. If you do the renovation to get those things and abide by the law, you will have to arrange a window too. In practice some individuals in overstaffed offices will work from a space that was originally storage, then negotiation room and now a shitty office room.