Chimney leak or roof leak

Where chimney leak water stains come from

Water enters a chimney four ways: through the cap, through a cracked crown, through lifted or rusted flashing, or through porous brick. The stain indoors only marks where the water ended up.

The trace

The check runs top-down: cap first, then crown, then the flashing band where the chimney meets the roof, then the brick face. A leak near the chimney is flashing until proven otherwise, because the flashing is the most common failure.

When it is the roof instead

If the stain sits far from the chimney or the attic shows water tracking along the rafters, the problem is a shingle or a roof penetration somewhere upstream. Describe where the stain actually is when you send the request.