Sealing a Brick Floor
I have a mortared brick floor in my great room with no finish on it. The floor tends to be gritty, and the adjacent wood floor is getting scratched. What should I use to seal it?
I have a mortared brick floor in my great room with no finish on it. The floor tends to be gritty, and the adjacent wood floor is getting scratched as we track the grit over it. Can I seal the brick, and if so, what should I use?
— Jim Echols, Jacksonville, Fla.
Kevin O'Connor replies: Leroy Danforth, an architectural engineer at the Brick Industry Association, tells me there are two types of products suitable for use on interior brick: film-forming products, which coat the brick surface, and penetrating sealers, which soak into the brick. Both types make a brick floor more stain resistant, but Danforth says that two coats of a film-forming product—either an acrylic or a polyurethane—will be most effective at solving the grit problem. Plus, they'll make it easier to clean the floor because they coat the surface and help fill the crevices that hold dirt. Acrylics are generally preferred over waxes or polyurethanes because they are easier to apply and less likely to yellow.
Just be aware that when you put a film-forming finish on brick, you can darken its color and give it a sheen. The only way to know how much a finish will alter the look of your brick is to test it on a sample or on an inconspicuous part of the floor. To minimize any change in appearance, try a penetrating sealer—after testing it—and be prepared to vacuum more frequently. Sealers are also easier to maintain; just reapply every year or so. Film-formers will last longer, but like most floor finishes, they need to be abraded before a new coat can be applied.