When installing three-tab shingles on a roof with a 4:12 pitch, how many nails must each shingle have at a minimum?

When installing three-tab shingles on a roof with a 4:12 pitch, the minimum requirement is to use four nails per shingle. This standard is established to ensure that the shingles are securely attached to the roof surface, providing maximum resistance against wind uplift, water infiltration, and potential damage from weather conditions.

Using four nails helps distribute the load across the shingles more effectively, particularly on roofs with a moderate pitch like 4:12. This pitch can create scenarios where shingles are more exposed to wind and other environmental stresses, so proper fastening is crucial. Each shingle should be nailed according to the manufacturer's specifications to maintain warranty coverage and to ensure the roof's longevity and performance.

Thus, four nails serve as a reliable standard for securing each shingle, enhancing the roof’s overall integrity and resistance to common roofing challenges.