How to Seal an Outdoor Brick Wall
- 1). Dust the surface of the brick wall with a push broom, removing dirt, cobwebs and other debris. If the wall has deeply recessed mortar joints, you might need to almost scrub the brickwork with the broom to reach the interior of the joints. Rinse the wall with a garden hose, and allow the wall to dry. Use a ladder if necessary.
- 2). Lay out a drop cloth at the foot of the wall, to protect nearby plants from harsh solvents and sealants.
- 3). Inspect the wall for splotches of paint or stains, such as any that might have been left behind during a roofing or window repair. Dissolve these with a masonry stain remover, and wipe away the residue with a wet rag. Stubborn stains might require scrubbing with a bristle brush.
- 4). Pour sealant into a paint pan or cup, and apply sealant to the wall with short, even up-and-down strokes. Use a paint roller if the wall is reasonably flat, but use a brush if the mortar joints are recessed, as the roller won't reach the interior of the joints. If you want to retain the original appearance of the brick wall use a clear sealant, but if you intend to paint the wall use a white masonry sealant. Use a ladder if necessary.
- 5). Wait three to four hours (or as directed by the label on the masonry sealant can) for the sealant to dry. Apply a second coat of sealant if you are using clear sealant. If you are going to be painting the wall, apply a second coat of sealant only if the first coat is splotchy or otherwise thin.