Stairs,
Landings, Handrails, Guardrails
(Single-Family Residential)
Stairways
must be constructed according to the requirements of
the California Building Code (2007 CBC Chapter 10) to
insure a safe means of access and egress.
Stairs:
A run of steps with two or more risers is a stairway.
Alternate
stairway types: Spiral stairs and winding stairs
are rarely used and therefore not discussed herein.
Refer to the building code for information on these
types of stairs.
Materials:
Exterior stairways, when constructed of wood, shall
be built with 2" nominal lumber. When exposed to
the elements, they shall be constructed of pressure
treated wood or wood with a natural resistance to decay
(i.e., redwood free of sapwood).
Width:
Stairways serving a single-family dwelling shall be
a minimum of 36" wide. Stringers, decorative trim,
etc., may project a maximum of 1-1/2" into the
required width from either side.
Rise
and Run: Maximum rise
shall be 7-3/4" and 10" minimum run at
stairs.
If
risers are solid and tread run is less than 11",
provide a 3/4" to 1-1/4" nosing.
The
rise and run shall be uniform with a maximum tolerance,
from the largest to the smallest riser or tread, of
3/8".
When
the top or bottom riser meets a sloping grade, the design
riser height shall be maintained at the centerline of
the stairway width.
Headroom:
All stairways shall have minimum headroom of 6-feet
8-inches measured vertically from the line of the tread
nosings to any soffit or projection above.
Loads:
Treads shall be capable of supporting a 300 lb. concentrated
load applied at any point. The stringers shall be capable
of supporting a 40-lb./sq. ft. uniform load.
Drainage:
Exterior steps and landings may be sloped not more than
1/4" per foot for drainage.
Landings:
Each stairway shall have a landing at the top and bottom
of the run of stairs. The landing dimension in the
direction of travel shall not be less than 36". For
stairways with a straight run, having a total rise
exceeding 12 feet, an intermediate landing shall be
provided. Landings
shall be at least as wide as the stairs.
Handrails
A
handrail shall:
· Have a gripable surface not less than 1-1/4"
and not more than 2" in cross-sectional dimension
or shall provide an equivalent gripping surface. Note:
Traditional handrail profiles that do not conform to
the 1-1/4"-2" dimensions may be acceptable;
check with the Building Division regarding the particular
installation.
· When projecting from a wall, a minimum 1-1/2"
space between the wall and the rail is required.
· Be installed and not less than 34" nor
more than 38" from the top of the rail to the line
of the nosings of the stairs.
· Have returned ends or rounded terminations
or bends.
· Be continuous the full length of each flight
of stairs and shall extend, as a minimum, from the bottom
riser to the top riser.
· Be so constructed that it is capable of supporting
a 200 lb. load applied at any point along the rail in
any direction
· Be required on one side only for stairways
serving individual dwelling units.
· Not be required for stairways having three
(3) or fewer treads serving individual dwelling units.
Guardrails:
Guardrails are required along open sides of stairways,
landings, balconies, porches, decks, floor openings,
ramps, and roofs used for other than service of the
building, which are more than 12" above grade.
Detailed
guardrail requirements:
·
Guardrails are required at the sides of stairways, landings,
ramps, porches, and balconies that are more than 12"
above grade or the floor below.
· Guardrails shall have a 42" minimum height,
42" high along open sides of stairways.
· Guardrails must be able to withstand a load
of 20 pounds per lineal foot applied horizontally at
the top of the guardrail.
· Intermediate rails, panels or fillers, and
their connections, shall be capable of withstanding
a load of 25 pounds per square foot applied at right
angles to the guardrail.
· Guardrails shall be designed so that a 6"
diameter sphere cannot pass through the triangular space
formed by the bottom of the rail, the riser and the
tread.
· Balusters on a handrail or a guardrail shall
be so spaced so that a 4" sphere cannot pass
through.
If you would like additional information,
please telephone the Building Division at (65) 991-8061
and ask to speak with a Building Inspector.

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