How to Repair a Brick Patio
If dealing with common problems, you can easily repair brick patios yourself. One common problem is sinking, which occurs gradually as a result of expansion and contraction in the ground due to changing weather conditions throughout the year. Another problem is weathered mortar that has either practically disappeared or is affected by cracks and chips. Either way, giving your patio a revamp through brick repairs should not be an arduous task.
Step 1 - Replacing Sinking Bricks Not Set in Mortar
Remove the sinking bricks with a chisel. Fill the space with gravel or sand and use a square tamper to compress it to provide a flat and level surface for the bricks. You may need to add or remove sand and tamper again to ensure that the new bricks are totally level with the rest of the patio. Place all the bricks back into their previous positions and sprinkle the patio with sand to about 1/2 inch in thickness. Use a broom to brush the sand into the cracks to complete the brick repairs.
Step 2 - Replacing Sinking Bricks Set in Mortar
Use a chisel to remove the problem bricks. Chip the mortar from the edges of the bricks you are lifting and around the settled bricks that surround them. Mix 1 part cement to 3 parts sand in a wheelbarrow, adding water whilst mixing, until the mixture turns to a muddy consistency. Lay a base of mortar about 1/2 inch thick into the void left by the removed bricks. Use the scrap of wood to level. Next, use a pointing trowel to apply mortar to the sides of the brick. Each layer should be about 3/4 inch thick. Push each brick into place on top of the base of mortar and make sure that they are tightly packed against the neighboring bricks. Once all the bricks have been replaced, use the pointing trowel to apply mortar between the tops of the bricks to finish. Brush away any excess mortar with a broom.
Step 3 - Replacing Missing Mortar
Give the area a thorough wash, preferably with a pressure washer. Cleaning the patio will enable you to see the particular type of mortar used on your patio. The color and size of the sand grains in the new mortar must match the original mortar. Once you have obtained the appropriate type of sand, mix 1 part sand to 1 part cement. As you would imagine, this ratio will produce a stronger mortar than the one described in the previous step. The extra strength is necessary for patch-up work such as this.
Wet the problem areas with a little water before filling half of the grout bag with mortar. Apply as much mortar as needed so that it exceeds the height of nearby bricks by about 1/4 inch. Once the mortar has lost its shine, use a trowel to scrape off any excess so that the applied mortar is level with the bricks surrounding it. Keeping the newly applied mortar damp for a couple days will help to ensure that it sets properly.