As a rule, granite is non-porous, which means it doesn’t need sealing. However, most fabricators recommend sealing and applying a sealer as extra protection to the natural stone during the fabrication process. During the granite countertop fabrication, a resin coating is applied to the stone countertop which fills and seals any natural fissures and veins on the stone surface. How often a granite countertop needs sealing depends upon certain factors.
- How often the countertop is used.
- How often the granite is cleaned.
- How porous the natural stone is.
- The type and quality of the previous sealer used.
Many sealers that are applied when stone countertops are fabricated last between 10 and 20 years. Store-bought sealers may only last for up to a year, so it is important to know if and which sealer has been previously applied in order to know when your granite countertop will need resealing
Using a simple water test to see how long it takes for water to be absorbed will tell you if the sealer is needed. Pour a quarter cup of water at a few different places on the granite countertop. If the water is absorbed into the stone within 5 minutes, then the stone needs sealing. If no water is absorbed in thirty minutes, then the stone doesn’t need any sealing. If the water is absorbed between 5 and 30 minutes then it may benefit it to use a sealer as extra protection.