In a current project, our specifications require the contractor to reuse old brick in a new building addition. The contractor doesn't want to reuse the brick because he fears it will deteriorate. Because the brick has been in the wall for 40 years and hasn't deteriorated, our firm thinks it shouldn't deteriorate in the new addition. Are the contractor's concerns justified?
The Brick Institute of America (BIA) discourages the use of salvaged brick. Though BIA is an association of manufacturers of new brick, in Technical Note 15, "Salvaged Brick," it gives two valid reasons for not reusing old brick. First, the surfaces of salvaged brick often are filled with mortar particles or dirt, which are difficult to remove completely. If the brick isn't cleaned completely, new mortar doesn't bond well to it. The poor joints that result lead to increased water penetration, which can subject the brick to a harsher exposure than it was subjected to before. Second, with salvaged brick, it's often difficult to separate the face brick from the backup brick. Both types might be mixed in the same stockpile, so brick that was in the backup of the old wall may end up on the surface of the new wall. This brick may not be durable. Though BIA doesn't mention it in the technical note, a third reason is that salvaged brick may respond differently to today's harder mortars than it did to the softer mortars of the past. Despite these precautions, salvaged brick can be used successfully--and often are required in restoration work. First check the governing building code. Many codes control the use of salvaged brick. Then, if you want to use it, be sure the brick is carefully sorted and tested. Salvaged brick should be tested for conformance to ASTM C 216, Standard Specification for Face Brick, and for bond strength.