How to Repair Leaky Chimney Flashing

The base of the chimney contains metal flashing. The flashing is there to keep roof leaks from happening. Sometimes the water can slope down the roof and get into cracks in the chimney, especially when the seals are damaged. They can be easily repaired within two hours.

How to Repair Leaky Chimney Flashing

Materials Needed

• Razor


• Wire brush


• Roof caulking


• Knife


• Paintbrush

1. Roof flashing sealant


2. Look around the entire base of the chimney to look for cracks in the chimney flashing. You will have to look closely because they cannot always be seen so easily.


3. Check the corners on the flashing as well the flashing area near the roof. The area of flashing that forms a corner is the area that is most prone to leaks.


4. Use a razor to remove the damaged caulking around the base of the chimney. Use your hand to remove the caulking after it is cut away from the base. Use a wire brush to clean the area. You want to make sure all of the pieces are swept away with the brush.


5. Cut open a tube of roof caulking with a knife. Make sure the opening is only ½ inch wide. Go around the base of the chimney and apply a new layer of roof caulking. You want to make sure as much caulk can come out of the hole so you can cut the hole much larger if you want.


6. Make sure the line of caulk is continuous with no gaps. This will create a much better seal. Allow the caulk to dry for 24 hours.


7. Go over the chimney flashing one more time with the caulk. Allow the caulk to dry for 24 hours.


8. Use a paintbrush to apply a layer of roof flashing sealant.