Mr. Inspector
SAWHORSE
2015 IMC. Inspecting a 4'x4' hatch on a roof on 2 story apartment building 12' from roof edge. They will use it to crane new HVAC units in the attic. I think the building was built around the civil war in a army base in PA. The roof hatch will be the only access to the attic. They will build a compliant ladder to the roof. From the vertical ladder to the roof hatch they want to have a ladder on the 3/12 sloped steel roof. Since the roof slope is less the required ladder for a 4/12 sloped roof does the ladder on top of the roof need to follow IMC 306.5 requirements for ladders? Section 306.5.1 for Sloped roofs only reference equipment actually on the roof.
306.5 Equipment and appliances on roofs or elevated
structures. Where equipment requiring access or appliances
are located on an elevated structure or the roof of a building
such that personnel will have to climb higher than 16 feet
4877 mm) above grade to access such equipment or appliances,
an interior or exterior means of access shall be provided.
Such access shall not require climbing over
obstructions greater than 30 inches (762 mm) in height or
walking on roofs having a slope greater than 4 units vertical
in 12 units horizontal (33-percent slope). Such access shall
not require the use of portable ladders. Where access involves
climbing over parapet walls, the height shall be measured to
the top of the parapet wall.
shall comply with the following minimum design criteria:
1. The side railing shall extend above the parapet or roof
edge not less than 30 inches (762 mm).
2. Ladders shall have rung spacing not to exceed 14
inches (356 mm) on center. The uppermost rung shall
be not greater than 24 inches (610 mm) below the
upper edge of the roof hatch, roof or parapet, as applicable.
3. Ladders shall have a toe spacing not less than 6 inches
(152 mm) deep.
4. There shall be not less than 18 inches (457 mm)
between rails.
5. Rungs shall have a diameter not less than 0.75-inch
(19 mm) and be capable of withstanding a 300-pound
(136.1 kg) load.
6. Ladders over 30 feet (9144 mm) in height shall be
provided with offset sections and landings capable of
withstanding 100 pounds per square foot (488.2 kg/
m2). Landing dimensions shall be not less than 18
inches (457 mm) and not less than the width of the
ladder served. A guard rail shall be provided on all
open sides of the landing.
7. Climbing clearance. The distance from the centerline
of the rungs to the nearest permanent object on the
climbing side of the ladder shall be not less than 30
inches (762 mm) measured perpendicular to the
rungs. This distance shall be maintained from the
point of ladder access to the bottom of the roof hatch.
A minimum clear width of 15 inches (381 mm) shall
be provided on both sides of the ladder measured
from the midpoint of and parallel with the rungs
except where cages or wells are installed.
8. Landing required. The ladder shall be provided with
a clear and unobstructed bottom landing area having a
minimum dimension of 30 inches (762 mm) by 30
inches (762 mm) centered in front of the ladder.
9. Ladders shall be protected against corrosion by
approved means.
10. Access to ladders shall be provided at all times.
Catwalks installed to provide the required access shall be
not less than 24 inches (610 mm) wide and shall have railings
as required for service platforms.
Exception: This section shall not apply to Group R-3
occupancies.
306.5 Equipment and appliances on roofs or elevated
structures. Where equipment requiring access or appliances
are located on an elevated structure or the roof of a building
such that personnel will have to climb higher than 16 feet
4877 mm) above grade to access such equipment or appliances,
an interior or exterior means of access shall be provided.
Such access shall not require climbing over
obstructions greater than 30 inches (762 mm) in height or
walking on roofs having a slope greater than 4 units vertical
in 12 units horizontal (33-percent slope). Such access shall
not require the use of portable ladders. Where access involves
climbing over parapet walls, the height shall be measured to
the top of the parapet wall.
shall comply with the following minimum design criteria:
1. The side railing shall extend above the parapet or roof
edge not less than 30 inches (762 mm).
2. Ladders shall have rung spacing not to exceed 14
inches (356 mm) on center. The uppermost rung shall
be not greater than 24 inches (610 mm) below the
upper edge of the roof hatch, roof or parapet, as applicable.
3. Ladders shall have a toe spacing not less than 6 inches
(152 mm) deep.
4. There shall be not less than 18 inches (457 mm)
between rails.
5. Rungs shall have a diameter not less than 0.75-inch
(19 mm) and be capable of withstanding a 300-pound
(136.1 kg) load.
6. Ladders over 30 feet (9144 mm) in height shall be
provided with offset sections and landings capable of
withstanding 100 pounds per square foot (488.2 kg/
m2). Landing dimensions shall be not less than 18
inches (457 mm) and not less than the width of the
ladder served. A guard rail shall be provided on all
open sides of the landing.
7. Climbing clearance. The distance from the centerline
of the rungs to the nearest permanent object on the
climbing side of the ladder shall be not less than 30
inches (762 mm) measured perpendicular to the
rungs. This distance shall be maintained from the
point of ladder access to the bottom of the roof hatch.
A minimum clear width of 15 inches (381 mm) shall
be provided on both sides of the ladder measured
from the midpoint of and parallel with the rungs
except where cages or wells are installed.
8. Landing required. The ladder shall be provided with
a clear and unobstructed bottom landing area having a
minimum dimension of 30 inches (762 mm) by 30
inches (762 mm) centered in front of the ladder.
9. Ladders shall be protected against corrosion by
approved means.
10. Access to ladders shall be provided at all times.
Catwalks installed to provide the required access shall be
not less than 24 inches (610 mm) wide and shall have railings
as required for service platforms.
Exception: This section shall not apply to Group R-3
occupancies.