Why Is My Roof Sagging After a Storm?

Storm winds and rain can force water under shingles or flashing, saturating the plywood or OSB roof deck. Once wet, the wood swells and loses strength, causing the roofline to dip. In cold, snowy winters, ice dams can trap water on the roof, adding weight and pushing moisture into the structure.

Heavy debris, like fallen branches, can also dent the roof surface and stress the framing. If the storm knocked down trees or power lines, the impact may have cracked trusses or rafters. A sagging roof is a serious sign that the load-bearing parts of your roof are compromised.

If the roof is sagging, keep everyone away from the affected area. A sagging roof can collapse without warning, especially after a storm. Turn off the electricity if water is near light fixtures or outlets, but only if you can do so safely. Otherwise, call an electrician.

Place a bucket under any active leak to catch water and prevent further damage to your floors and belongings. You may need to move furniture and valuables out of the room. Do not attempt to fix the roof yourself; this is a job for professionals with the right safety equipment.

After repairs, keep your roof clear of leaves and debris to prevent water pooling. Check your gutters and downspouts regularly to ensure they are not clogged. In cold climates, consider improving attic insulation and ventilation to reduce ice dam formation.

If you live in Detroit, keep a roof inspection schedule in mind after major storms. A quick visual check from the ground can catch loose shingles or damaged flashing early. Address small issues before they become big ones, as a well-maintained roof is less likely to sag.