Limestone can be cleaned effectively with the right materials. It is a sedimentary rock that does not tolerate acids or harsh cleansers; therefore, most household chemicals are out of the question. Counter tops, floors, walls and a variety of other building materials are made from limestone. The calcite stone is porous and can be easily scratched or stained, but with the right products and proper cleaning methods, you can maintain your limestone surfaces.
Unpolished or polished limestone
The cleaning methods are very similar for unpolished and polished limestone. Choose a limestone cleaner that has a solvent-based impregnator that helps remove deep debris from your stone. Check the label to be sure that you're using the correct type of limestone cleaner. The wrong type of solution may contain active ingredients that can ruin your finish. Before cleaning floors, use a soft bristled broom to sweep up all dirt and scattered debris. Use a soft cloth to clean limestone counter tops.
Clean outdoor limestone walls with a pressure washer on a low setting and a commercial cleaner that is specific for limestone cleaning. Choose a day when temperatures are above 21 degrees C (70F), to allow adequate drying time. Because the stone is porous, saturated limestone takes a day or a little more to completely dry out. Wash stone walls down by making quick water sweeps with the pressure washer. Apply the cleaner to the stone and follow the product's directions. Maintain outside limestone walls by power washing them twice a year.
Limestone stain removal
Improperly sealed or unpolished limestone items stains easily. Buy a stain removing product, such as poultice, at your local hardware shop to clean stains on limestone. Poultice is a powdered substance that is mixed with water and smeared over the stain. Use a clean cloth to wipe the stone free of dust. Apply the poultice limestone cleaner as per the packet directions. Allow it to sit over the stain for at least 24 hours, and then wipe up thoroughly. With a clean, damp washcloth, wipe away any remaining debris.
Daily limestone care
Clean limestone daily by sweeping up dirt and other debris to prevent scratches from forming. Use a soft bristled broom to prevent nicks and grazes in the stone. Lightly mop with tap water or a special formulated limestone cleaner twice a week for maintenance. Wipe up spills immediately to prevent liquids from soaking in. Apply a limestone sealer from a stone supplier or hardware shop annually to counter tops and every other year to flooring tiles to maintain. Never use vinegar, lemon juice or other acids for limestone cleaning. These items will erode your stone and cause acid etching.