Questions and Answers for Rust-Oleum 1 gal. Concrete Low Lustre Sealer (Case of 2)

A:  First and most importantly, make sure no previous sealer is present. Preparation of a block wall with Rust-Oleum Concrete Sealer is the same as directions for the floor. Start by cleaning the surface thoroughly and etching it as much as possible for the vertical surface. After you allow the surface to dry, wipe your fingers over the surface, if any dust or powder is present on your finger, repeat the cleaning until this no longer happens.