Sagging Roof Deck
in Charlotte, NC

Charlotte's average annual rainfall of approximately 43 inches, combined with summers where relative humidity frequently exceeds 80 percent, means that any unresolved roof leak saturates OSB or plywood sheathing repeatedly over multiple seasons, and OSB in particular loses its structural integrity rapidly once its outer paper facing delaminates from prolonged wetting. Rotted sheathing loses the ability to transfer roof loads to the framing below and begins to deflect between rafter bays, creating the sagging, wavy appearance visible from the street.

Many Charlotte homes built in the 1960s and 1970s in neighborhoods like Eastover, Cotswold, and South Charlotte used conventionally framed rafter systems that were designed to specific load assumptions, and decades of moisture cycling in poorly ventilated attics can cause the structural members themselves to crack, split, or lose bearing capacity. Additionally, amateur attic storage of heavy materials or previous owner modifications that cut through rafter spans without proper headers have compromised the structural integrity of the framing in a significant number of older Charlotte homes.

While Charlotte does not experience prolonged winters, the periodic winter ice storms and brief freezes that affect the Piedmont — particularly in elevated areas of northern Mecklenburg and southern Iredell County — can create ice dams at eave overhangs when poorly ventilated attic heat melts snow that refreezes at the cold eave edge. The resulting pooled water is forced under shingles and into sheathing, and even one season of repeated ice dam events can introduce enough moisture to begin fungal decay in the decking.