Making new brick match old brick is a process that will require staining the brick. Staining should only be tackled in the case where a perfect match can not be located. The process to stain the brick is a complicated one that is not easily mastered without prior knowledge of the pigments and how they work. The process is simplified with a chart that is included with most products. The chart will explain the pigment combination to accomplish a specific colour. After the stain has been mixed and applied, it will last approximately 20 years depending on the product.
Wash each new brick with an organic degreaser. Scrub the bricks with a nylon brush. Ensure that all grease, oil, dirt, debris, and other materials have been removed from the bricks. Rinse each brick with water. Allow them to completely dry over night before continuing.
Mix the brick stain according to manufacturer's directions. The instructions will include an amount of pigment needed to result in a specific colour. To accomplish the exact colour needed to match the existing brick, this process with need to be altered and repeated several times.
Apply the stain to a spare brick by brushing the solution onto the brick using a paint brush the same size as the brick. Wait six hours after applying the first layer before applying additional coats. Apply several variations of stain to several bricks to determine the best match. Allow each one to rest for seven days to allow the stain to cure. Number each brick and write down the mixture used on that specific brick. This will be needed later to replicate it, if it is the colour needed.
Stand the spare bricks up against the existing brick. Step back approximately 20 feet to determine which one of the new bricks are the best match to the existing brick. If none are close repeat the process.
Apply a sealer to the brick only in situations where the brick will be installed in high traffic areas like driveways, and sidewalks.
Always wear gloves when working with the chemicals.