Roofing Inspection

Per IRC R803, roof sheathing must be minimum 7/16" OSB or 15/32" plywood. Per IRC R905.1, underlayment is required under all asphalt shingles. Ice barrier per IRC R905.1.2 is required from eave edge to 24" inside the exterior wall line in areas with history of ice damming.

1. Verify sheathing thickness and type meet code requirements

2. Check for proper H-clips between sheathing panels (if required by span)

3. Verify underlayment is installed over entire roof deck

4. Check ice and water shield at eaves, valleys, and penetrations

5. Confirm sheathing is securely fastened with no waviness or soft spots

- Insufficient sheathing thickness for rafter spacing

- Missing ice and water shield in required areas

- Wrinkled or improperly lapped underlayment

- Soft spots from water damage before roofing installed

Per IRC R905.2, asphalt shingles must be installed per manufacturer specifications. Standard exposure is 5" for 3-tab and 5-5/8" for architectural shingles. Minimum 4 nails per shingle (6 in high-wind areas). Nails must be in the nailing zone per manufacturer.

1. Verify shingle exposure is consistent and per manufacturer specs

2. Check that shingles are straight and properly aligned

3. Verify starter course at eaves with adhesive strip facing up

4. Check nail placement — must be in manufacturer's nailing zone

5. Inspect for proper offset between courses (min 6" for 3-tab)

- High-nailing (nails above nailing zone — shingles can blow off)

- Inconsistent exposure creating wavy appearance

- Missing starter course at eaves

- Improper offset creating pattern alignment issues

Per IRC R903.2, flashing is required at wall-roof intersections, valleys, chimneys, dormers, and all roof penetrations. Step flashing per IRC R903.2.1 must be minimum 4" × 4" at wall intersections. Valley flashing must extend minimum 8" from centerline.

1. Inspect step flashing at all wall-to-roof intersections

2. Verify valley flashing extends minimum 8" from center

3. Check chimney flashing — must have step flashing on sides and counter-flashing

4. Inspect pipe boots and vent flashings for proper seal

5. Verify drip edge at eaves and rakes

- Missing step flashing at walls (most common leak source)

- Improper valley flashing or exposed fasteners in valleys

- Failed pipe boot seals

- Missing or improperly installed drip edge