Most exterior limestone will have a honed finish, for which using a mild soap is the best option for regular cleaning. But if you have polished limestone outdoors, use a pH-neutral detergent, such as a mild dish soap, in place of the castile soap. [3] X Research source Make sure not to apply any acidic cleaners to the limestone! Limestone can easily become damaged when exposed to acidic solutions. Keep cleaning agents like vinegar or lemon juice away from your floors. [4] X Research source If you’re using a store-bought detergent for limestone, follow the instructions on the product. Different products require different amounts of water, and you should stick to the product guidelines in order to avoid harming your limestone.
Make sure that you remove any bird excrement before deep cleaning! If it’s exposed to a heavy cleaning solution, it can permanently stain your limestone. [9] X Trustworthy Source U. S. General Services Administration Independent U. S. government agency designed to support the basic functioning of the U. S. federal government. Go to source
If you’re using a power washer, be sure not to use too much pressure. Anything over 1200 psi could damage your limestone. [11] X Trustworthy Source U. S. General Services Administration Independent U. S. government agency designed to support the basic functioning of the U. S. federal government. Go to source
An alkaline cleaner can work especially well to remove berry and other stains that get on exterior limestone. Alkaline cleaners break down fatty, greasy, and oily deposits, and are far safer for limestone than acidic cleaners. [13] X Research source Different alkaline cleaners may require different amounts of time on the limestone surface. Follow the product’s instructions for the best results. [14] X Research source
If you have plants near your limestone floor, try not to get too much of the cleaning solution on them. Depending on how hardy your plants are, they could be harmed by the strength of the alkaline cleaner. If you’re worried about their safety, you can set up a plastic tarp on the edge of your limestone to stop any water from entering the soil. [16] X Trustworthy Source U. S. General Services Administration Independent U. S. government agency designed to support the basic functioning of the U. S. federal government. Go to source
Be sure not to set the pressure too high. Anything about 1200 psi could damage your wall. [21] X Research source Depending on the kind of detergent you buy, the amount you should add to your power washer will differ. Consult the product guidelines for more information. If you’re renting your power washer, ask beforehand whether the model allows for detergent to be added. Different power washers have different capacities for detergent, so you may need to refill it while washing.
