"Oil, water, juice, ink—any liquids or spills, really—can soak in and stain granite," says Emily Long, a home improvement expert with SafeWise.
To keep this from happening, most granite countertops are covered in a sealant. But this layer can wear off over time, so it's up to you to reapply as needed. Luckily, sealing granite countertops is something most homeowners can do themselves by purchasing granite sealant at their local hardware store. If you want your granite to continue looking great and last for ages, check out these steps on how to seal granite countertops.
The answer to this depends on what type of stone you have installed in your kitchen.
"For a lighter-colored stone—which is typically more porous—you should generally seal it once a year," says Long. Darker, harder stones can be sealed once every 10 years, or may not need to be sealed at all.
To find out if your granite countertop needs to be sealed again, simply sprinkle a few drops of water on its surface. If the water beads up, the seal is strong. If the drops pool, that means the seal is compromised and should be reapplied.
Whatever you do, don't seal your countertops if they don’t need it “just for extra protection,” as this can create a cloudy residue that’s difficult to remove. But if your countertop is in need of more sealant, proceed!
Here's how to seal granite countertops.
First, clear everything off your countertops. Clean the granite with water and dish soap or granite cleaner and a lint-free cloth (like a microfiber cloth or an old T-shirt). Let it dry completely before you start the sealing process.
Choose a penetrating sealer specifically made for granite, or at least for natural stone. Before sealing your countertops, spray a small section in an inconspicuous corner. Make sure there’s no discoloration or residue before you continue.
While you should read the instructions on your bottle, for most sealers, you start by spraying a generous coat evenly over the surface of your countertops. Make sure you’ve covered the entire surface, with no dry spots left.
Once the countertop is completely covered in a layer of sealant, let it sit. After 15 to 20 minutes, while the sealer is still wet, wipe the surface with a lint-free cloth to mop up the excess.