BP Exterior Cement Primer is a specially formulated value-for-money acrylic primer for application on exterior masonry surfaces. This is ideal for markets with low to medium rainfall.BP Exterior Cement Primer is prepared with a special grade of acrylic binder and pigment that provides extra whiteness with excellent opacity. It reduces porosity of the wall which thereby reduces efflorescence. It forms a water resistant film on the surface which prevents water and dissolved salts from penetrating the film. It protects the top coat from damage and helps to provide longer life of the total paint system. It penetrates the porous surface, reduces the absorption of the surface and as a result, top coat gives better coverage.