Minimum Roof Hatch Opening Size

Recommended minimum sizes for various types of roof access are shown above.

Minimum roof hatch opening size.

If movement of bulky materials through the hatch is anticipated double leaf hatches with openings up to 66 sq. Attics with mechanical equipment. In buildings without an occupied roof access to the roof shall be permitted to be a roof hatch or trap door not less than 16 square feet 1 5m2 in area and having a minimum dimension of 2 feet 610 mm. When a hatch is left in the open position personnel working atop a roof can lose their footing trip over the hatch s curb or even step backward into the areaway without looking thereby sustaining debilitating or even fatal injuries.

Per osha 1910 23 d 2 the minimum perpendicular distance from the centerline of the steps or rungs or grab bars or both to the nearest permanent object in back of the ladder is 7 inches. Ft openings as the standard for various structures. Or larger are available. To provide adequate clearance for emergency personnel and protect workers from injury while using the hatch osha specifies a minimum clearance of 30 between the centerline of the ladder rungs to the back edge hinged side of the hatch opening.

This 7 inch minimum stand off clearance protects the person climbing the ladder from likely trip hazards that would exist with less free space between the. Roof hatches bilco roof hatches provide safe and convenient access to roof areas by means of an interior ladder ship stair or service stair. A variety of special sizes are also available to provide an accessible way to install or remove large pieces of equipment from a building. The rough framed opening must measure a minimum of 22 by 30 inches.

All open roof hatches regardless of size or number of covers can present fall hazards. If the opening is located in a wall it must be at least 22 inches wide and 30 inches high. Recent changes to the international building code require 16 sq. A common size of roof hatch is 36 x 30 for ladder access to the roof however that size does not meet this osha standard.