How to Seal Masonry to Prevent Leaks

Chimney leaks are actually very common; and, in most cases, touching up the sealant around the flashing is all that’s really needed. But if the leak persists no matter what, it can simply be water migrating in through the masonry surface.

Both the bricks and mortar are very porous. In addition to causing water leaks inside, as the mortar absorbs the water, it expands. That is why you’ll often see cracking all along the mortar lines.

A good quality masonry sealer is the solution. It can be applied to the surface using a garden pump-up sprayer. The sealer keeps water from soaking into the pores, which effectively completely stops the leak.

It also protects the surface against dirt and stains, and even helps prevent that chalky white residue you see a lot of times on brick surfaces.


  1. We have leak in walls &ceiling around chimney for the past four years.We have at least six different slate roofers try to fix it. they charged thousands of dollars then they say we cannot find the reason.flashing is new no roofer removed all slates around chimney&put new under layer.The severity of leak is reduced but it is not completely gone.Now no roofer returns the phone calls any more.WE are at wits end.Your response would be highly appreciated


Please enter your comment!
Please enter your name here