07/31/2026
A bead of caulk over a leaking roof flashing buys you one Texas summer. By August it cracks in the heat, and the leak is back.
Here in Austin we see it every year. Someone runs sealant along the step flashing on a chimney or a wall. It holds through the spring rain, then the sun bakes the caulk until it splits, and water goes right back behind it into the decking.
Flashing does its job by shape, not by stickiness. It is bent metal that laps under the shingles and over the joint so water sheds off the roof. A real repair pulls the old flashing, checks the wood underneath, and sets fresh metal the right way. Caulk is the last inch of that job, never the whole job.
If a roofer looks at a flashing leak and reaches for a tube of sealant, ask what happens next August.