DampStop Injection
The plaster goes on before the injection. First the old, damp plaster is stripped, then HydroFix damp-proofing plaster is applied. Once the plaster has dried (24–48 hours), the holes are drilled and DampStop is injected. After the injection, wait at least 48 hours, then fill the holes with plaster or mortar; painting comes last. Why this order? Stripping plaster can break open the cells of the bricks; if you inject first, the solution runs out through those breaks. If the plaster goes on first, the injection stays inside the brick without overflowing.