Railing Projects
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Building Codes – general information
and guidelines
Municipal
and state authorities generally do not write their own code. They use these model codes and guidelines to create
documents for use in their local
jurisdictions.
Not all fabrications need to meet
building codes. Some installations may be considered ornamental in nature. It is imperative that you familiarize
yourself with local code requirements prior to specifying or purchasing any
products from BuyRailings web site.
Most municipalities and local code
bodies do not write code – they adopt codes prepared by various code
organizations. Historically, model codes were published by code organizations
such as the Building Officials Code Administrators International, Inc. (BOCA),
the Council of American Building Officials (CABO), the International Conference
of Building Officials (ICBO), and the Southern Building Code Congress
International (SBCCI).
ICC
Prior to 2000, BOCA, SBCCI and ICBO
each prepared their own model codes that were regionally applied. In 1999,
these three organizations began to work together to prepare a unified code
under the auspices of the International Code Council (ICC). The first set of I Codes were published in 2000 and included
the International Residential Code (IRC) and the International
Building Code (IBC). The 2000 IRC and IBC model codes have since been
adopted by states throughout the country. In 2002, BOCA, SBCCI and ICBO officially
merged to form the ICC and they approved an updated IRC and IBC most recently
published in 2006.
Handrail and Guardrail
Handrails are in place to provide
guidance while the purpose of a guardrail is to prevent accidental falls.
Guards are generally required for ramps, stairs or landings above 30".
The height will vary depending on
the code. The IBC requires a guard to be 42" in height. Handrails are
located between 34" and 38" and have dimensional limitations for graspability. As such, if a 42" guardrail is called
for on a stair or ramp, it will also require a secondary handrail at the
appropriate height. A guard top rail that is not used as a handrail would not
have a graspability size limitation. Guards also have opening limitations to
consider. The most common requirement is that no opening be large enough to
allow a 4" sphere to pass.
The Ladder Effect
The published 2000 IRC stated that
guardrails shall not be constructed with horizontal members or other
ornamental pattern that results in a ladder effect. The ladder effect has
never been a part of the IBC. The ladder effect was removed from
the IRC during the 2001 code cycle. The change was noted in the 2001 IRC
supplement and the current 2003 IRC contains no reference to the ladder
effect.
However, some local code authorities
are using older codes based on BOCA – the creator of the ladder effect wording
– and the 2000 IRC. Many local code
inspectors are not aware of the 2001 change and may reject guardrailings with infills they interpret as creating a ladder
effect. It is taking time for the 2001 IRC supplement and the new 2006
model codes to trickle down to the local levels. In the meantime, be prepared
to address this issue should it come up in your area.
The following information is based
on Code Restrictions from IRC, IBC, ANSI and ADAAG
Guardrail Location Requirements
IRC 2000 30 inch (762mm)
above floor or grade below.
IRC 2003 R312.1 Guards required. Porches,
balconies or raised floor surfaces located more than 30 inches (762 mm) above
the floor or grade below shall have guards not less than 36 inches (914mm) in
height. Open sides of stairs with a total rise of more than 30 inches (762 mm)
above the floor or grade below shall have guards not less than 34 inches (864
mm) in height measured vertically from the nosing of the treads. Porches and
decks which are enclosed with insect screening shall be provided with guards
where the walking surface is located more than 30 inches (762 mm) above the
floor or grade below.
IBC 2000 Open-sided walking surfaces,
mezzanines, industrial equipment platforms, stairways, ramps and landings more
than 30 inches (762mm) above floor or grade below. Also located along glazed
sides of stairways, ramps and landings that are located more than 30 inches (762mm)
above floor or grade below where the glazing provided does not meet the
strength and attachment requirements in Section 1607.7 Live Load.
IBC 2001 Amended to add the following: Exemption 2: The height in assembly seating
areas shall be in accordance with Section 1008.12.
IBC 2003 Amended to add the following: Exemption 7. In assembly seating where guards
in accordance with Section 1024.14 are permitted and provided.
Handrail Location Requirements
IRC 2000 Handrails required on at least one
side of ramps exceeding a slope of 1:12. Handrail required on at least
one side of stairway.
IRC 2001 Handrail required on at least one
side of stairway with two or more risers.
IRC 2003Handrails shall be provided on at
least one side of each continuous run of treads or flight with four or more
risers.
IBC 2000 Handrails required on both sides of
stairs and ramps.
IBC 2001 Amended to add the following: Aisle
stairs complying with Section 1008 provided with a center handrail need not
have additional handrails.
IBC 2003 1009.11 Handrails. Stairways shall
have handrails on each side. Handrails shall be adequate in strength and
attachment in accordance with Section 1607.7. Handrails for ramps, where
required by Section 1010.8, shall comply with this section.
Exceptions:
1. Aisle stairs complying with Section 1024
provided with a center handrail need not have additional handrails.
2. Stairways within dwelling units, spiral
stairways and aisle stairs serving seating only on one side are permitted to
have a handrail on one side only.
3. Decks, patios and walkways that have a
single change in elevation where the landing depth on each side of the change
of elevation is greater than what is required for a landing do not require
handrails.
4. In Group R-3 occupancies, a change in
elevation consisting of a single riser at an entrance or egress door does not
require handrails.
5. Changes in room elevations of only one
riser within dwelling units and sleeping units in Group R-2 and R-3 occupancies
do not require handrails.
ANSI A117.1 Handrails required
on both sides of stairs and ramps.
EXCEPTION: Aisle stairs and aisle ramps
provided with a handrail either at the side or within the aisle width.
ADAAG Ramps - both sides,
if rise exceeds 6 inches or a horizontal length more than 72 inches. Not required next
to seating in assembly areas. Stairs - both sides.
Live Load, Uniform
IRC 2000 50 lbs/ft
IRC 2003 200 lb. Uniform
Live Load. Guard in-fill components (all those except the handrail), balusters and panel
fillers shall be designed to withstand a horizontally applied normal load of 50
pounds on an area equal to 1 square foot. This load need not be assumed to act
concurrently with any other live load requirement.
IBC 2000 50 lbs/ft in any
direction (handrails and guards).
IBC 2003 Handrail assemblies and guards shall
be designed to resist a load of 50 plf (0.73 kN/m) applied in any direction at the top and to transfer
this load through the supports to the structure. 1607.7.1.2 Components.
Intermediate rails (all those except the handrail), balusters and panel fillers
shall be designed to withstand a horizontally applied normal load of 50 pounds
(0.22 kN) on an area equal to 1 square foot
(0.093m2), including openings and space between rails. Reactions due to this loading
are not required to be superimposed with those of Section 1607.7.1 or
1607.7.1.1.
Live Load, Concentrated
IRC 2000 200 lbs
IRC 2003 200 lb Uniform Live
Load. A single concentrated load applied in any direction at any point along the top.
IBC 2000 200 lbs In any direction (handrails and guards).
IBC 2003 Handrail assemblies and guards shall
be able to resist a single concentrated load of 200 pounds (0.89 kN), applied in any direction at
any point along the top, and have attachment devices and supporting structure
to transfer this loading to appropriate structural elements of the building.
ANSI A117.1 250 lbs (grab bars
for toilets, tubs and showers)
Allowable Opening, Maximum
IRC 20004" sphere - general; 6"
sphere - at triangle formed by riser, tread and bottom rail. Required guards shall not be constructed with
horizontal rails or other ornamental pattern that results in a ladder effect.
IRC 2001 4" sphere - general; 6"
sphere - at triangle formed by riser, tread and bottom rail. Ladder Effect removed.
IRC 2003 R312.2 Guard opening limitations. Required
guards on open sides of stairways, raised floor areas, balconies and porches
shall have intermediate rails or ornamental closures which do not allow passage
of a sphere 4 inches (102mm) or more in diameter.
Exceptions:
1. The triangular openings formed by the
riser, tread and bottom rail of a guard at the open side of a stairway are
permitted to be of such a size that a sphere 6 inches (152 mm) cannot pass
through.
2. Openings for required guards on the sides
of stair treads shall not allow a sphere 43/8 inches (107mm) to pass through.
IBC 2000 4" sphere –
general - to a height of 34"; 6" sphere - at triangle formed by
riser, tread and bottom rail; 8" sphere from a height of 34" to
42".
Exceptions: 21" sphere for elevated
walk for electrical, mechanical and plumbing systems and Group I-3, F, H, or S
occupancies, balusters, horizontal intermediate rails or other construction.
IBC 2003 3. In areas which are
not open to the public within occupancies in Group I-3, F, H or S, balusters,
horizontal intermediate rails or other construction shall not permit a sphere
with a diameter of 21 inches (533 mm) to pass through any opening.4. In
assembly seating areas, guards at the end of aisles where they terminate at a
fascia of boxes, balconies and galleries shall have balusters or ornamental
patterns such that a 4-inch-diameter (102 mm) sphere cannot pass through any
opening up to a height of 26 inches (660 mm). From a height of 26 inches (660
mm) to 42 inches (1067mm) above the adjacent walking surfaces, a sphere 8
inches (203 mm) in diameter shall not pass.
Height Requirements, Minimum for Handrails
IRC 2000 Measured vertically above stair nosings and ramp surfaces: 34" minimum; 38"
maximum.
IRC 2003 Handrail height, measured vertically
from the sloped plane adjoining the tread nosing, or finish surface of ramp
slope, shall be not less than 34 inches (864mm) and not more than 38 inches (965
mm).
IBC 2000 Guards not less than 42 inches with
Exception: For Group R-3, and within individual dwelling units in R-2,
whose top rail also serves as handrail shall have a height not less than 34
inches and not more than 38 inches.
ANSI A117.1 Measured vertically
above stair nosings and ramp surfaces: 34"
minimum; 38" maximum.
ADAAG 38" maximum.
ADAAG Advisory: The requirements for stair
and ramp handrails in this document are for adults. When children are the principle users in a
building or facility (e.g., elementary schools), a second set of handrails at
an appropriate height can assist them and aid in preventing accidents. A
maximum height of 28 inches (710 mm) measured to the top of the gripping
surface from the ramp surface or stair nosing is recommended for handrails
designed for children. Sufficient vertical clearance between upper and lower
handrails, 9 inches (230 mm) minimum, should be provided to help prevent
entrapment.
Height Requirements, Minimum for Guardrails
IRC 2000 36" (residential) - porches,
balconies, raised floor surfaces 34" minimum on open side of stairs.
IBC 2000 42" except where top rail also
serves as a handrail it shall have a height not less than 34" and not more
than 38".
IBC 2001 Amended to add the following: The height in assembly areas shall be in
accordance with Section 1008.12.
IBC 2003 Amended to add the following:
Exemption 2: The height in assembly areas
shall be in accordance with Section 1024.14.
Height Requirements (of Guardrails) For
Balconies, Galleries & Bleachers
IBC 2000 All portions of the stairway width
required for egress capacity are within 30 inches (762mm) of a handrail.
IBC 2003 Intermediate handrails are required
so that all portions of the stairway width required for egress capacity are
within 30 inches (762 mm) of a handrail. On monumental stairs, handrails shall be
located along the most direct path of egress travel.
End Details, Handrails
IRC 2000 Ends shall return or shall terminate
in newel posts or safety terminals
IBC 2000 Return to wall, guard or the walking
surface or continuous to the handrail of an adjacent stair flight
ANSI A117.1 Return to wall,
guard or the walking surface or continuous to the handrail of an adjacent stair
flight
ADAAG Return smoothly to walls, posts or
floors.
Wall Clearance
IRC 2000 1-1/2 inch minimum.
IRC 2003 1-1/2 inch (38mm) minimum between
wall and the handrail
IBC 2000 1-1/2 inch minimum.
IBC 2003 Clear space between a handrail and a
wall or other surface shall be a minimum of 1.50 inches (38mm). A handrail and
a wall or other surface adjacent to the handrail shall be free of any sharp or
abrasive elements.
ANSI A117.1 1-1/2 inch minimum.
ADAAG 1-1/2 inch minimum.
Project from Wall
IBC 2000 4.50" maximum.
IBC 2003 4.50" maximum.
Intermediate Handrail Requirements
IRC 2000 All portions of the stairway width
required for egress capacity are within 30" of a handrail.
IRC 2003 Intermediate handrails are required
so that all portions of the stairway width required for egress capacity are
within 30 inches (762 mm) of a handrail. On monumental stairs, handrails shall be
located along the most direct path of egress travel.
Grip Size, Handrail
IRC 2000 Circular shapes: 1.25" minimum
2.625" maximum. Non-Circular: Other shapes that provide an equivalent
grasping surface are permissible. Edges shall have .125" minimum radius.
IRC 2001 Type 1: Circular shapes: 1.25 inch
minimum 2.625" maximum.
Type 2: Handrails with a perimeter greater
than 6.25" shall provide a graspable finger recess area on both sides of
the profile. The finger recess shall begin within a distance of .750"
vertically from the tallest portion of the profile and achieve a depth of at
least .031" within .875" below the widest portion of the profile.
This required depth shall continue for at least .375" to a level that is
not less than 1.75" below the tallest portion of the profile. The minimum
width of the handrail above the recess shall be 1.25" to a maximum of
2.75". Edges shall have a minimum radius of .010".
IRC 2003 Type I. Handrails with a circular
cross section shall have an outside diameter of at least 1-1/4 inches (32mm)
and not greater than 2 inches (51 mm). If the handrail is not circular it shall
have a perimeter dimension of at least 4 inches (102 mm) and not greater than
6-1/4 inches (160 mm) with a maximum cross section of dimension of 2-1/4 inches
(57 mm). Type II. Handrails with a perimeter greater than 6-1/4 inches (160mm)shall provide a graspable finger recess area on both sides
of the profile. The finger recess shall begin within a distance of ¾ inch (19
mm) measured vertically from the tallest portion of the profile and achieve a
depth of at least 5/16 inch (8mm) within 7/8 inch (22mm) below the widest
portion of the profile. This required depth shall continue for at least 3/8
inch (10mm) to a level that is not less than 13/4 inches (45 mm) below the
tallest portion of the profile. The minimum width of the handrail above the
recess shall be 1-1/4 inches (32 mm) to a maximum of 23/4 inches (70mm). Edges shall
have a minimum radius of .01 inches (.25 mm).
IBC 2000 Circular shapes: 1.25" minimum
2" maximum. Non-Circular: Perimeter dimension 4" minimum a 6.25"
maximum and 2.25" maximum cross-section. Edges shall have .125"
minimum radius.
IBC 2001 No change to dimensions other than
following: Edges shall have a minimum radius of .010".
IBC 2003 1009.11.3 Handrail graspability. Handrails with a circular cross section
shall have an outside diameter of at least 1.25 inches (32 mm) and not
greater than 2 inches (51 mm) or shall provide equivalent graspability. If the handrail is not circular, it shall
have a perimeter dimension of at least 4 inches (102 mm) and not greater
than 6.25 inches (160 mm) with a maximum cross-section dimension of 2.25
inches (57mm). Edges shall have a minimum radius of .01 inch (.25mm). Exception 3: Handrail brackets or
balusters attached to the bottom surface of the handrail that do not
project horizontally beyond the sides of the handrail within 1.50 inches (38
mm) of the bottom of the handrail shall not be considered to be
obstructions and provided further that for each .50 inch (13 mm) of
additional handrail perimeter dimension above 4 inches (102mm), the vertical
clearance dimension of 1.5 inches (38 mm) shall be permitted to be
reduced by .125 inch (3 mm).
ANSI A117.1 and ADAAG Circular shapes:
1-1/4 inch (32mm) minimum; 2 inch (51mm) maximum. Non-Circular: Perimeter dimension 4 inch
(100mm) minimum and 6-1/4 inch (160mm) maximum and 2-1/4 inch (57 mm) maximum
cross-section. Edges shall be “rounded”.
Extension Requirements at Ends
IRC 2003 R311.5.6.2
Continuity. Handrails for stairways shall be continuous for the full length of the flight,
from a point directly above the top riser of the flight to a point directly
above lowest riser of the flight. Handrail ends shall be returned or shall
terminate in newel posts or safety terminals. Handrails adjacent to a wall
shall have a space of not less than 1-1/2 inch (38mm) between the wall and the handrails.
Exceptions:
1. Handrails shall be permitted to be
interrupted by a newel post at the turn.
2. The use of a volute, turnout, starting
easing or starting newel shall be allowed over the lowest tread.
IBC 2000 12"
horizontally beyond top stair riser. Bottom of a stair flight, handrail shall
extend at the slope of the stair flight for a horizontal distance equal to one
tread depth beyond the last riser nosing. No extension required (residential).
IBC 2003 1009.11.4
Continuity. Handrail-gripping surfaces shall be continuous, without interruption by newel
posts or other obstructions.
Exceptions:
1. Handrails within dwelling units are
permitted to be interrupted by a newel post at a stair landing.
2. Within a dwelling unit, the use of a
volute, turnout or starting easing is allowed on the lowest tread.
3. Handrail brackets or balusters attached
to the bottom surface of the handrail that do not project horizontally beyond
the sides of the handrail within 1.50 inches (38 mm) of the bottom of the handrail
shall not be considered to be obstructions and provided further that for each
.50 inch (13 mm) of additional handrail perimeter dimension above 4 inches
(102mm), the vertical clearance dimension of 1.50 inches (38 mm) shall be
permitted to be reduced by .125 inch (3 mm).
ANSI A117.1 12"
horizontally beyond top stair riser. Bottom of a stair flight, handrail shall
extend at the slope of the stair flight for a horizontal distance equal to one
tread depth beyond the last riser nosing. 12"
horizontally after slope at bottom. 12"
horizontally minimum beyond top and bottom of ramp runs.
ADAAG12" horizontal at both top and
bottom of ramp runs.
Sources:
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