Current through Register Vol. 49, No. 13, September 23, 2024
Subpart 1.
IRC section R311.3.2, Floor elevations for other exterior doors.
Section 311.3.2 is amended to read as follows:
R311.3.2
Floor elevations for other
exterior doors. Doors other than the required egress door shall be
provided with landings or floors not more than 7-3/4 inches (196 mm) below the
top of the threshold.
Exception: A landing is not required if a stairway
less than 30 inches (762 mm) in height is located on the exterior side of the
door, provided the door does not swing over the stairway. The stairway height
shall be measured vertically from the interior floor surface to the finished
grade.
Subp. 2.
IRC section R311.7.1, Width.
Section R311.7.1 is deleted and replaced with the
following:
R311.7.1
Stairways;
general.
R311.7.1.1
Stairways serving dwellings or accessory structures. All stairways
serving a dwelling or accessory structure, or any part thereof, shall comply
with this section. This shall include exterior stairs from a dwelling or garage
to grade and those stairs serving decks, porches, balconies, sun rooms, and
similar structures.
Exceptions:
1. Stairs serving attics or crawl
spaces.
2. Stairs that only provide
access to plumbing, mechanical, or electrical equipment.
R311.7.1.2
Width. Stairways
shall not be less than 36 inches (914 mm) in clear width at all points above
the permitted handrail height and below the required headroom height. Handrails
shall not project more than 4.5 inches (114 mm) on either side of the stairway
and the minimum clear width of the stairway at and below the handrail height,
including treads and landings, shall not be less than 31-1/2 inches (787 mm)
where a handrail is installed on one side and 27 inches (698 mm) where
handrails are provided on both sides.
Exception: The width of spiral stairways shall be
in accordance with Section R311.7.10.1.
Subp. 3.
IRC section R311.7.2,
Headroom.
Section R311.7.2 is amended to read as follows:
R311.7.2
Headroom. The minimum
headroom in all parts of the stairway shall not be less than 6 feet 8 inches
(2032 mm) measured vertically from the sloped line adjoining the tread nosing
or from the floor surface of the landing or platform on that portion of the
stairway.
Exceptions:
1. Where the nosings of treads at the side of
a flight extend under the edge of a floor opening through which the stair
passes, the floor opening shall be allowed to project horizontally into the
required headroom a maximum of 4-3/4 inches (121 mm).
2. The minimum headroom for existing
buildings shall be in accordance with section R305.2.2.
3. The headroom for spiral stairways shall be
in accordance with Section R311.7.10.1.
