Bathroom Doorway Recommendation: 32″
To obtain a minimum clear opening of 32″ a door of minimum 34″ width is required. A minimum clear width of 34″ is the universal design. The absolute smallest allowable opening is 24″, but only if the existing walls prohibit any modifications.
How to measure a door’s clear opening? If you measure from doorjamb-to-doorjamb when the door is open, this measure the door’s opening but not the door’s clear opening. To calculating the clear opening, measure from the inside of the door to the other side of the opening while the door is open. Usually, this clear opening measurement will be around 2 inches less than the door opening. Ignore doorknobs when taking these measurements.