Minn. R. 4658.4455
CEILING HEIGHTS; NEW CONSTRUCTION
Minimum ceiling heights must be provided as follows in items A to C. A. Boiler room ceilings must be at least five feet higher than the top of the boiler unit and at least two feet, six inches above the main boiler head and connecting piping with a minimum total height of nine feet. B. Ceilings in corridors, storage rooms, resident toilet rooms, and other minor rooms must not be less than seven feet, six inches. C. Ceilings in all other rooms must not be less than eight feet.