Repairing a Block Wall Veneer

Pull away the loose veneer and mortar, scrubbing the block surface with a stiff brush to remove any loose material.

Clean off the bricks using a wire brush. If the mortar adhered to the brick and not the blocks, you may find it easier to repair the damage with new bricks instead of trying to break off the mortar.

Mix a batch of mortar in a wheelbarrow or bucket, depending on the size of the repair. Add only enough water to make a thick puddinglike consistency, stirring with a trowel or a garden hoe.

Trowel over the block wall with a 1/2-inch notched trowel, working only a small area at a time.

Butter, or cover, the back of a brick with mortar. Press the brick into place, leaving room for a 3/8-inch gap for grouting between the bricks. Twist the brick slightly to make good contact between the brick and the block wall. Continue to fill in the damaged area with clean brick veneer.

Leave vertical gaps called weep holes in the mortar between bricks at the top and bottom of any windows or doorways. Since bricks are porous, water enters the bricks from rain. Weep holes allow the water to drain wherever there is flashing below the bricks -- normally at the tops and bottoms of any openings in the wall. This is part of the building code for most municipalities and keeps water from building up in the bricks.

Fill in the gaps between the bricks using a mortar bag filled with the same mortar that you used to attach the bricks. On the bricks where you formed the weep holes in the mortar, don't add any more mortar between the bricks. Press the mortar into the rest of the gaps with a joint tool until the surfaces of the joints are smooth.

Clean off any excess mortar on the surface of the bricks with a stiff brush.