How to Fix Holes in Mortar

Put on a pair of work gloves, safety glasses and a dust mask.

Place the edge of a flat-head chisel against the edge of the mortar surrounding the hole or crack.

Tap the back end of the chisel with hammer to knock out the mortar inside the joint. Continue tapping the chisel and removing old mortar until you have removed between 3/4 inch to 1 inch from the surface. Make sure you remove enough mortar until the edge of the mortar is flat and free from damage. The new mortar will bond best with a flat surface.

Mix a bag of mortar mix with water according to the product instructions. Use a wheelbarrow or a cement tub to mix the mortar. Stir the mixture thoroughly with a shovel.

Load some mortar onto the top of a brick trowel. Place the edge of the trowel against the bottom edge of the joint from which you removed the damaged mortar.

Scrape 1/4-inch wide lines of mortar into the brick joints using a 3/8-inch wide pointing trowel. Fill the horizontal joints first, then fill the vertical joints. Pack the mortar into the joints tightly. For joints deeper than 3/4 inch, allow half of the mortar to dry slightly, then fill in the rest of the joint later.

Drive a 6d box nail into a small block of wood until the head sticks outs 1/4 inch. Rake the joints with the head of the nail to create indentations to match the rest of the mortar joints.