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Quick Tips Windows

Caulk Between Window Sill And Masonry Ledge‏

Question: I have read two, opposite opinions about whether one should caulk between a windowsill and a masonry ledge under it. It is a 60-year-old brick and block house, and the window sills do not reach to the outside surface of the brick. Instead, there is a masonry ledge beneath the sill that goes past the brick. The ledge is slanted for drainage.

One opinion I have read says not to caulk the joint to allow drainage. The other opinion, of course, says to caulk the joint.

BTW, most of the sills are in good shape and are made of cedar. Rot on some of the sills has been removed and repaired by splicing in solid PVC. In those cases, only the PVC is in contact with the ledges.

Answer: You do not want to caulk that joint, it is there to provide drainage to the outside of the window. If you caulk you will end up with water on the inside wall and floor.