Limestone Stain Removal

One of the more popular materials for an outdoor patio is limestone. Whether the patio is made from pavers, small bricks, or a single large flagstone it is becoming more and more common to see limestone in the backyards of homes across the country. Interestingly enough, as many of these homeowners can attest to, limestone presents unique difficulties when it comes to cleaning.

Limestone is extremely porous when compared to other kinds of stone. As such, limestone stain removal can be a little tricky. You cannot exactly use the same tactics in limestone stain removal that you would if cleaning a concrete patio. Instead, use these step-by-step instructions and you should have a clean, stain-free limestone patio.

1. Gather. When cleaning your limestone patio, you will need to gather a few simple items. You will need a pressure washer (which can be rented from any home improvement store), a deck broom, regular broom, dustpan, stiff brush (not a wire brush), goggles, rubber gloves, small bucket, and bleach.
2. Sweep. Sweep off your patio completely. Start by using the deck broom and sweep everything into large piles. After you have a pile of all the dirt and grime that was on your patio, use your smaller regular broom and a dustpan to remove the piles. Continue this until the vast majority of the dirt has been removed.
3. Rinse. Set up the pressure washer according to the instructions that came with it. Put on the goggles to help protect your eyes and turn the pressure washer on. Many times, simply rinsing off the patio with a pressure washer will remove the vast majority of stains. However, if this does not prove to be the case, then proceed to step four.
4. Scrub. Put on your rubber gloves and grab the stiff brush and your bleach. Pour some of the bleach into a bucket and fill the rest of the bucket with water. (The proper mixture should be roughly one part bleach to three parts water.) Pour a little of the cleaning mixture onto the stain and proceed to scrub away with the stiff brush. Repeat this as necessary until the stains are removed.
5. Rinse. Turn your pressure washer back on. Rinse off the entire patio to help remove any standing cleaning mixtures, while also removing the last vestiges of any stains. If this does not work, repeat step four again until the stains have been completely removed.

All that is left to do is allow the patio to dry. Now you can sit back and enjoy your freshly cleaned patio. I would suggest having a few friends over to have a nice little outdoor party.

Keep in mind that you should never use any type of acid to clean limestone. If you remember high school chemistry, limestone is calcium based and acids don't mix well with calcium. If you use an acid (i.e., muriatic acid) to try cleaning your limestone patio you will end up with a chemical reaction similar to the old vinegar and baking soda volcanoes, which could really damage your patio.