Try Surface Grouting
Surface grouting is an option to consider. The process consists of applying a thin coat of cement-based grout to the mortar joints and the mortar/brick interface. The Brick Institute of America recommends a mixture of 1 part portland cement, 1/3 part lime, and 1 1/3 parts fine silica sand. Premixed, proprietary surface grouting mortars also are available.
Step by Step
- Mask grouting should be done only when the outside air temperature is at least 50 degrees Fahrenheit. The recommended procedure is as follows. Fill small holes and repair any seriously deteriorated mortar joints.
- Cover the brick faces with strips of masking tape as wide as the height of the brick.
- Place dry grout material in a clean container and gradually add clean water, stirring until the mixture has the consistency of thick batter.
- Dampen the mortar joint surfaces, but leave no free water. Then, following the joint lines, apply the grout with a coarse fibered brush.
- Carefully strip the masking tape before the grout sets.
Surface grouting is not a panacea for every leaky brick wall, but it can be an effective repair method for some of them.