Is a missing shingle a big deal?

A single missing shingle may seem minor, but it can be a big deal depending on location and weather exposure. Asphalt shingles are installed in an overlapping system where each shingle covers the nails and seams of the row below. When one shingle is missing, it breaks this water-shedding system and exposes the underlayment and potentially the seam below to direct rain. If the missing shingle is in the field of the roof in a non-critical area and underlayment is still intact, it is not an immediate emergency during dry weather, but it should be fixed within a few days to a week. If the missing shingle is in a valley, along a ridge, near flashing around a chimney or vent, or if it exposes bare wood decking, it is a big deal and should be tarped within 24 hours. Even a small gap can allow wind-driven rain to get under surrounding shingles and cause them to lift, expanding the damage quickly. Over time, water intrusion can lead to decking rot, attic mold, and interior ceiling stains that cost far more than a simple shingle replacement. From an insurance perspective, ignoring a missing shingle can be considered failure to mitigate damage, which could jeopardize a future claim. So while one missing shingle is not catastrophic, it should never be ignored.