In this video, This Old House general contractor Tom Silva replaces crumbling, missing mortar.
Steps for repointing a brick foundation
- Spread a drop cloth at the base of the brick wall.
- Use a pointed raking bar to scratch the mortar from the horizontal bed joints between the rows of bricks. Remove one more than 1 inch of mortar.
- Remove the mortar from the vertical head joints with a brick chisel and masonry hammer. Tap out the mortar to a depth of 1 inch, being careful not to chip any bricks.
- Use the chisel to rake out any loose mortar or dust from the head joints.
- Remove any cracked or badly damaged bricks, then rake out all the old mortar.
- Roll up and move the drop cloth out of the way. Discard the old mortar raked from the joints.
- Spray the wall with a garden hose, lightly wetting the entire repair area, including the raked out joints.
- Into a wheelbarrow dump one bag of mortar mix. Add water and then mix with a shovel or hoe.
- Scoop some mortar from the wheelbarrow with a brick trowel and place it onto a small square of plywood.
- Lay the drop cloth in front of the wall to catch any dropped mortar.
- To install a full brick, use the trowel to lay down a thick setting bed of mortar onto the brick below.
- Apply mortar to the end of a full brick, and also to its top surface. Slide the brick into place, making sure to maintain mortar joints consistent with the rest of the wall.
- Tap the brick down, if necessary, to align it flush with the adjacent bricks.
- Use a narrow tuck pointer to tightly pack mortar into the vertical bed joints between the rows of bricks.
- Next, use a masonry jointer to force mortar into the horizontal head joints between the bricks.
- Once all the joints have been repointed, strike off the mortar with the jointer to tool and smooth the mortar.