Roofing Safety, Codes, and Plan Reading
Roofing Safety, Codes, and Plan Reading
This domain tests the jobsite safety rules OSHA enforces, the code edition your inspection follows, and your ability to turn a roof plan into quantities and details.
- Fall protection: federal OSHA requires protection when a worker is exposed to a fall of 6 feet or more, and at the edge of a low-slope roof. Options include guardrail systems, safety-net systems, and personal fall-arrest systems anchored for the load. Training and a rescue plan are part of the rule, not extras.
- Access: ladders extend 3 feet above the landing, set at a 4:1 angle, and secured. Skylights and roof openings get covers or guardrails rated for the load.
- Mississippi has no OSHA-approved State Plan covering private employers, so federal OSHA rules govern roofing crews. Roof inspections are driven by local codes, not state statute: confirm the edition of the IRC or IBC your authority having jurisdiction enforces.
- Plan reading: a roof plan shows ridges, hips, valleys, slopes (such as 6:12), penetrations, drains, and dimensions. Sections and details give flashing heights and layer build-up; schedules name materials. Estimate in squares of 100 square feet, applying a pitch multiplier and a waste factor.
Worked example. A roof plan measures 40 feet by 30 feet, or 1,200 square feet in plan. At 6:12 the pitch multiplier is 1.118, so sloped area is 1,342 square feet. Add 10% waste: 1,476 square feet, or 14.8 squares. Order 15 squares plus starter, ridge cap, and valley metal measured in linear feet.
Traps. Using plan area as roof area; forgetting overhangs and waste; treating 10 feet as the fall-protection trigger; assuming a code edition without checking with the AHJ; and forgetting that ridge, hip, valley, and drip edge are linear-foot takeoffs, not squares.