Granite has a particular level of porosity, so it needs to be sealed after it is installed. You can either hire a company that specializes in sealing granite countertops, or you can do it yourself. Here is a 101 on the granite countertop sealing.
But before your start …
Remember that not all granite countertops have to be sealed. How do you know if yours needs sealing? Do this simple test: put several drops of water on your granite countertop’s surface. Time how long it takes the water to get absorbed. If absorption time is under three to four minutes, your granite countertop probably needs to be sealed. If absorption time is longer, it probably does not need sealing.
You can also leave two drops of water on your granite countertop for about 30 minutes, and then wipe the water off. If your granite is already sufficiently sealed, it will not spot. If it spots, you need to seal it.
Using penetrating sealers
Penetrating sealers (better known in the industry as impregnators) are oil-based, so they get absorbed deep and fast. They protect the structure of granite and all other natural stones, for that matter. These oil-based sealers ‘protect from within.’ They are fairly simple to use, so you can seal your granite using them yourself. Penetrating sealers are spread over directly on the surface of the granite countertop, preferably with a soft cloth. They break in below the granite’s but do not leave any film or coat on top. What does this mean? That the inner stone is protected, but the surface is not. Penetrating sealers are enough for granite (which is a very hard natural stone), but may be lacking for calcareous stones like onyx, marble, travertine, and limestone. These kinds of natural stone may still dull and even etch when acid (such as those from orange juice) are left on their surface.
How to apply oil based granite sealer properly
Work in sections of about four to five square feet so you can apply the sealer more evenly.
Gently apply the oil based sealer into your granite countertop using a soft rag. You may also use a soft brush.
Wait about three to four minutes until the oil based sealer is absorbed.
It’s time to do a second coating when your sealer is almost dry. Put on just a little more (less than what you applied earlier) and rub it in gently using a soft, clean rag.
Repeat the same procedure on the other sections of your granite countertop until you have sealed its entirety.
Wait about two hours then repeat the process from the beginning. The time it will take for the sealer to be absorbed will depend on its brand – some seal faster while others take longer. Read the instruction manual to be sure.;
Granite sealer brands
There are many granite sealers in the market. Below are just two of the most popular:
Hydrex. The petroleum-based Hydrex is known for making granite countertops water- and oil-repellent. It penetrates stone surfaces deeply and does not alter the granite’s color. Drying time is also quite fast – you only need to wait about 30 minutes. Hydrex comes in aerosol spray cans. Most granite countertop factories use it.
Granite Skudo. Skudo is a water based sealer made specifically for granite (it is not suitable for marble). Some experts say that because it is water based, it does not penetrate as fast and as deeply as the oil based Hydrex, though. The upside? Skudo has no fumes and leaves no smell. It can also make your granite countertop water- and oil repellent. Like Hydrex, Skudo does not affect the granite’s color. If you are sensitive to chemical smells, the Skudo is the right sealer for you.
Oil based sealers provide great protection for your granite countertop, but they are not enough – you also have to regularly clean your countertop if you want to make sure that it stays new-looking longer. Always have stone soap ready (or any natural vegetable soap cleansers will do). They are available in almost all hardware stores. Stone soaps form a thin layer of film between regular deep cleanings. They get rid of debris and dirt from your granite countertop’s surface just like detergent soap does, except that they are a lot milder and safer.