Answer-((Yes,))topical sealers generally can be applied over most penetrating sealers. Penetrating sealers generally do not form a membrane, film, or barrier that would prevent the topical sealers from adhering to the surface. As a matter of fact, most penetrating sealers were originally developed for use as primers to be applied prior to topical coatings and sealers being applied. It was only in recent years that penetrating sealers gained popularity for usage as a standalone product due to their inherent properties for preserving, protecting, and strengthening concrete, brick, and stone surfaces. Please consult product label and product specification sheet for specific details on the product you are considering.
Can penetrating concrete sealers be applied over topical sealers?
No, topical sealers create a membrane, film, or barrier that prevents the penetrating sealers from absorbing into the surface. If intention is to apply a penetrating sealer to a surface, then it will be necessary to properly remove the topical sealer from the surface prior to application of the penetrating sealer. Removal may be accomplished through scraping, grinding, sand blasting, shot blasting, pressure washing, chemical stripping, or other accepted method