A brick wall may be painted provided the correct preparation is done, the proper paint is selected, and the paint is applied correctly. Generally, new brick walls are not painted. However, if it is desired to paint a recently constructed brick wall, the wall should be allowed to fully cure 28 days and should not be cleaned or treated with acid solutions. Alkali-resistant paints should be used and a zinc chloride or zinc sulfate solution may need to be applied to the wall to neutralize the surface. Painting brick does not preclude good construction and detailing practices. Any deficiencies such as surface deposits; broken brick; cracked, loose or missing mortar; or inadequate flashing and weep holes should be corrected prior to painting. In addition, the brick should be thoroughly cleaned and given ample time to dry before application of paint. See Technical Notes 7F and 20 for more information. For brickwork to function properly, the wall must resist moisture penetration and be permeable to vapor from the structure. Consequently, any paint applied to the wall must also have these same characteristics. In addition, the inherent features of a brick wall which channel water out, such as weep holes and vents, must not be clogged by paint or caulk to inhibit the flow of water. Latex and portland cement-based paints perform well on brick walls. Oil-based, alkyd, rubber and epoxy paints do not allow any vapor in the wall to escape and consequently should not be applied to brick. Prior to painting, the brick should receive a prime coat suitable for the paint application per manufacturer's instructions. For additional information on painting brick masonry, see Technical Notes 6.