Brick or cement floors in open terraces or on driveways or garden paths have a tendency to grow moss, particularly after constant rain. This does not only mar their appearance but can make brick and cement dangerously slippery especially if it is somewhat damp.
To remedy it, scrub brick or concrete floor with a strong solution of chlorine bleach and rinse well, or spray the moss with a solution of Ammate which is available in some hardware or home depot stores.
Following are other tips on removing certain stains from floors:
Adhesive used for laying new floors
Remove adhesive with steel wool and a solution of all-purpose liquid cleaner and kerosene, then rinse. On asphalt or rubber floors, use alcohol.
Rub off burn with sudsy water, or a solution of all-purpose liquid cleaner. If stain is old, place over it an absorbent cloth saturated with a solution of 1 part glycerin and 3 or 4 parts of water. Let stand for about half an hour. Repeat if necessary. If the stain has soaked into a porous floor, such as marble or granolithic, terrazzo or cement tiles use hydrogen peroxide solution.
Soak tiles with kerosene about two hours if persistent, or rub with kerosene then wash with soap and water. You may also use a solution of oxalic acid, and then clean with a solution of all-purpose cleaner.
Remove with putty knife. The tar may be softened for easier removal with naphta or kerosene, then scrub with a fine steel wool and a solution of all purpose liquid cleaner.
To minimize floor staining, wipe spills immediately. If floor is properly protected with wax many stains will be kept on the surface and will not penetrate.