Here are the parameters you have to work within based on the residential edition of the florida building code fbc r305 and the international residential code irc.
Headroom clearance for stairs.
Because the toilet fits in at the low side of the sloped ceiling under the stairs the vertical clearance in front of it is the primary issue.
Stairway headroom or overhead clearance.
Maximum 7 3 4 inch stair riser height.
Handrail graspability to be either type i or ii with a minimum 1 1 2 inch clearance from a wall.
Friday june 15 2018.
Specifications for stairway overhead clearance.
Spiral stairs must meet the vertical clearance requirements in paragraph d 3 of this section.
1 for a room with a sloped ceiling at least half of the ceiling must be a minimum of 7 feet or higher with no part of the required floor area lower than 5 feet.
The distance from the top of the stair tread to the ceiling above measured at the stair tread nose should be six feet eight inches or more.
Vertical clearance above any stair tread to any overhead obstruction is at least 6 feet 8 inches 203 cm as measured from the leading edge of the tread.
Stairway headroom should be 6 8 over tread or landing.
Stairway headroom should be 6 8 over tread or landing.
Minimum 10 inch stair tread depth with nosing or minimum 11 inches with no nosing.
1910 25 b 3 stairs have uniform riser heights and tread depths between landings.