Why should we seal natural stones?

Why should we seal natural stones?

Posted by Mike Hernandez on Mar 31st 2023

I get this question asked frequently. Why should we seal If it is a natural stone, then it should last forever. Well, this is true for most stones but some stones area not native to the area and the weather has severe impact on the life of the stone. Other stones have been engineer and the are more open to weather impact. (Engineered stones are stones cut to make them look like tiles). Usually, stone walkways, driveways, pool decks, patios are built over a sand base and then the gaps between the stones are filled with sand, polymeric sand or mortar. When exposed to high heat, rain, snow or ice the stones will tend to expand and compress this movement will separate the mortar from the edges of the stone and then allow water penetration to the base. A humid sand base will shift depending on the weather exposure allowing the stones move horizontally and vertically eventually destroying the stone (shedding) and the retaining mortar.

We recommend sealing the stones with a penetrating sealer like SealGreen Brick and Natural Stone Sealer with Salt Defense Technology. Why?

  • 1.The sealer is a penetrating sealer and will not make the stones slippery when wet or change the look of the stones.
  • 2.The sealer reduces the expansion and compression of the stones when exposed to the weather.
  • 3.The sealer will prevent the movement of the stones horizontally and vertically because it does not allow the stones and mortar to absorb water and soak the base.
  • 4.The sealer will also reduce shedding if the stone is not native to the area.
  • 5.It will also keep your stones looking cleaner.
  • 6.We recommend washing the stones with SealGreen Mold and Mildew Remover before sealing
  • 7.It is important to make sure that the walkway has good drainage around it to prevent water sipping under the stones.