Depending on where you have had sandstone pavers laid in your home, you may find that some areas are prone to developing mold over time. This is especially prevalent in bathrooms, patios, pool areas and even kitchens. Mold develops in these areas because sandstone has a porous surface that absorbs mold spores, which will grow if in contact with enough water. Since some molds are toxic to humans and pets, and they cause an ugly discolouration to your sandstone, it is always preferable to remove the growth as soon as possible.
Before treating sandstone for mold growth, it is important to always wear rubber gloves, safety goggles and the proper respirator to ensure that mold spores do not settle in your body and cause serious health problems. You should also remember to wet sandstone mold before scrubbing it, as this will help to prevent spores from being released into the environment and spreading.
For this treatment, you will need to mix together equal parts of chlorine bleach and water in a spray bottle. Spray a generous amount of this solution onto the mold and leave on the sandstone for 10 – 15 minutes. Spray the sandstone for a second time. Then, scrub at the mold using a stiff-bristled scrubbing brush and finish by rinsing with clean water. You are able to repeat this treatment if necessary.
For this treatment, you will need to buy a commercial antimicrobial spray, available at most supermarkets. Spray it onto the moldy sections of your sandstone. If the area you are treating is quite large, rent a fogger, which will allow the antimicrobial mist to settle on the mold more quickly than manually spraying it. Leave the spray to dry completely, as it forms an airtight coating over the top of the sandstone that actually suffocates the mold. Next, soak an old rag in the antimicrobial spray and use it to scrub at the sandstone to remove the dead mold.
For this treatment, you will need to purchase some hydrogen peroxide solutions of varying strength. Pour a solution of 3% onto the mold and scrub it with a soft bristled brush. Sometimes, the mold becomes deeply embedded within the sandstone, requiring you to undergo more than one treatment. Remember to let the sandstone dry between each treatment. If the mold problem has not been fixed, however, repeat using a solution of 35% hydrogen peroxide.
Once you have killed off the mold and moss growth in your sandstone, you will need to ensure that you have it resealed to prevent the growth returning. Even though you can remove mold from sandstone, the process involves the use of some chemicals that are less than desirable for human inhalation, so should not be consistently applied.