Removing Calcium build Up from non-calcite exterior stone.

By Frederick M Hueston, StoneForensics.com

Removing white calcium buildup from exterior stone can be a difficult task, but it is doable with the right tools and techniques. Here are some steps to take in order to remove white calcium from exterior stone:

1. Begin by combining one cup of sulfamic acid with one gallon of water. This will produce a mild acid solution that will aid in the breakdown of the calcium buildup.
2. Using a spray bottle or a brush, apply the solution to the affected area of the stone. Make sure to thoroughly saturate the area.
3. Allow at least 15 minutes for the solution to sit on the stone. This will allow the acid to penetrate the calcium buildup and begin to break it down.
4. Scrub the affected area with a stiff-bristled brush. To remove as much calcium buildup as possible, apply firm pressure and scrub in a circular motion.
5. Thoroughly rinse the area with water to remove any remaining solution and debris. Once all the calcium is removed neutralize with a neutral cleaner.
6. Repeat steps 2–5 as needed to remove the calcium buildup.

It’s important to note that the steps above are only guidelines; depending on the type of stone, the severity of the stain, and the type of calcium deposit, some stones may require more aggressive acids like hydrochloric.

A mild acid solution, a stiff-bristled brush, and some elbow grease are required to remove white calcium buildup from exterior stone. You can restore the beauty of your exterior stone and protect it from future damage with patience and persistence.

Caution: Do not use this method on calcium based stone such as limestone or marble. There are removers that are non acidic that are available from your stone equipment suppliers.

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