Why is my roof leaking by the chimney?
Read where the water shows up
- Stain on the uphill side of the chimney: water is piling up behind it. Wide chimneys without a cricket are the usual cause.
- Stain along one side: step flashing or counterflashing on that side, often where the counterflashing was surface mounted with caulk instead of set into the mortar.
- Water at the fireplace or inside the firebox: rain is getting in through the top, a cracked crown, missing cap or open flue, and it is not a roof flashing problem.
- Damp wall around the chimney a day after rain: often water absorbed by the brick itself, especially on older chimneys with eroded mortar.
Read when it happens
A leak in every rain suggests an open hole, such as a lifted flashing piece or a missing cap. A leak only in heavy or wind-driven storms suggests water overrunning short flashing, a missing cricket, or rain driven into porous masonry. A leak that keeps dripping long after the rain stops usually means water stored in the brick or in soaked insulation.
What a real fix looks like
The shingles along the chimney come off, new step flashing is woven in one piece per course, an apron goes across the front, a cricket is built behind any chimney wider than 30 inches, and new counterflashing is cut into the mortar joints. A tube of roof cement over the old joint can stop a drip for a season, but Georgia heat cracks it quickly. Have the crown and cap checked at the same time so you are not chasing two leaks. See chimney leaks and crickets and common roof leak causes.