Waterproofing sealers penetrate into the surface of the brick where they chemically react to form a hydrophobic barrier within the pores. They won't change the look or color of the brick or stone, and they won't leave behind a surface film or coating.
Waterproofing can help stop leaks before they happen with preventative waterproofing. Maintaining the mortar joints in high maintenance areas and keeping the surface protected with waterproofing will ensure a prolonged life to the home or building, keeping it free of major repairs in the future. Thus, reducing the cost of future repairs.