Floating ceiling - it suits this space as it is a high space, it could work too…
These thin strips of wood make elegant panelling. By using it along the height of the wall and up onto the ceiling, they make this small cloakroom look much more spacious.
Decorative Drop Ceiling Panels | Home Designs
Stella McCartney's restored Victorian floorboards
Wood panelling, walls and ceilings all painted by NGI
White Kitchen with Wood Ceiling
Walls/floor/oak working beautifully together
Fixed window then pillar before doors. Perhaps with fan light to let in some air without opening main doors?
Office_Assemble Studio_Ceiling Design!