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Marble damage by soft water

Most people are familiar with hard water damage on natural stone, but did you know that soft water can also damage certain types of natural stone? Read on to learn more about soft water damage and what can be done to protect your stone.

About Hard and Soft Water Damage

Hard water damage to natural stone is a buildup on the stone’s surface caused by mineral deposits. One would imagine that having a water softening system installed would protect natural stone. Although it is true that soft water will eliminate the problem of mineral deposits on stone, soft water can create an entirely new problem. Lacking in minerals, soft water pulls minerals from natural stone. If your stone is marble or some other soft, calcium-based stone, soft water can degrade and dissolve your stone.

Where Stone Is Used Makes a Difference

Obviously, there is no cause for concern when it comes to natural stone applications that rarely get water exposure, such as walls in an entryway or a fireplace mantel. Floors that are damp-mopped, countertops that are cleaned with a damp cloth, conference room table tops, and other surfaces that see minimal water exposure will probably do fine, as well. Kitchen countertops near the kitchen sink and surfaces that are constantly being wiped down, such as commercial bar tops and restaurant table tops may see some degradation, although this will happen very slowly over the course of a long period of time. The major problem area for both hard and soft water issues is bathroom showers, because the stone is exposed to an average of two gallons of water per minute every time someone showers.

Solutions to Minimize Soft Water Damage

Consider using silicate-based stones, such as granite, sandstone, slate, and quartzite where water exposure is excessive. If your stone is already in place, consider the following suggestions.

Use potassium chloride instead of sodium chloride pellets to soften your water.

Another option is to have a reverse osmosis drinking water system installed along with your water softener. Reverse osmosis removes over 95% of “everything” in the water, including sodium.

Since water with salts removed will dissolve soft calcium based stones, you will also need to have the stone sealed to reduce softening. The catch-22 is that sealing stone in moist environments may not always be advisable. Ask your stone restoration technician to give specific recommendations for your stone.

This is one of a series of articles written and published on behalf of Surface Care PRO Partners.