My roof flashing is leaking. What can I do to fix it?

Fixing a leaking roof flashing around a chimney, skylight, or vent pipe requires sealing gaps where water penetrates joints. First, clean away dirt, debris, and old cracked roofing cement from the flashing seams using a stiff wire brush. Second, if the metal flashing pieces are rusted through or warped, remove the fasteners and install a brand-new flashing kit integrated properly beneath the shingles. Third, for minor gaps, apply a thick, heavy bead of exterior-grade polyurethane roofing sealant or asphalt flashing cement along all exposed joints and overlapping seams. You can troubleshoot roof safety safely by working on a dry, low-slope roof with proper fall protection. You can verify that your corrective action is successful when sealing the joints stops water from dripping into the attic space during subsequent heavy rainstorms.