As a general rule of thumb, we recommend resealing every 2-3 years. While some experts recommend sealing granite annually, most in the industry agree that granite can simply be sealed as needed. However, due to granite's high natural porosity, it's important not to go too long between sealings.
Why Do Stone Countertops Need Sealing? Natural stone material such as granite and marble is porous, and if left unsealed, will allow liquids to seep in and cause damage. Keep in mind that the more porous the stone, the more susceptible it is to liquid damage and stains.
Unlike granite, quartz doesn't need to be sealed on a regular basis in order to prevent staining. The nonporous surface makes it an ideal choice for food preparation and maintenance. You can clean these countertops with some warm and soapy water when necessary.
Water Will Discolor Them
Even something as simple as leaving a cold glass with condensation on your unsealed counters can change them. That's because water can penetrate the stone and leave behind water marks, permanently altering the appearance of your counters and potentially making them look dirty.
When you don't seal your countertops, they tend to quickly absorb food and liquids, leading to deep stains. Since the countertops are bare, the stains develop within a matter of minutes, even if you are quick to wipe the spill. The countertops not only absorb liquids, but grease and pigments as well.
A simple water test will help you determine if sealer is needed. Pour about a quarter cup of water on a few areas of the counter. See how long it takes for the water to absorb. If the water absorbs into the stone in less than five minutes, the stone does need to be sealed.
It is like any other natural material. Wood has its grain, and stone has its pores. Fortunately, it's easy to seal a granite countertop. It takes just a few minutes and requires little more than a granite sealer and a clean pad.
Typically, granite should be resealed every 12 to 18 months. Nevertheless, there are some other factors that come into play when determining how often to reseal granite countertops. For example, a lighter colored granite will need to be resealed more often because it is typically more porous.
A few '15-year' sealants are some of the best chemically engineered sealers available. They penetrate deeply into the stone and provide superior water & oil repellency. However, like all sealers, '15- year' sealers cannot prevent etching and unfortunately, they do not prevent stains for 15 years either.
Apply a drop of water 1 inch in diameter to the stone surface. Allow the water to stand on the stone for 5-30 minutes. If the surface is unsealed, the water will absorb into the stone and darken the surface (absorption speed will depend on porosity of the stone).
If after a few minutes the water has soaked into the granite, then it's time to reseal the stone. DON'T: Use harsh or abrasive cleaners and sponges. Windex; acidic cleaners, like vinegar, lemon, lime; or anything with ammonia or bleach should be avoided.
Choosing the Right Sealant is Essential
For this reason, look for products in the class known as impregnating stone sealers. They are chosen by professional contractors for sealing granite, marble, and slate countertops. The top-rated product in this class is Tenax Hydrex Impregnating Stone Sealer.
Quartz countertops are the easiest natural stone to take care of. They are engineered using ground stone and resin, so they don't require regular sealing they way most granite and marble countertops do. This stone is non-porous, so it does not easily stain or etch.
Sealing your stone kitchen countertops is an investment in the future of your home. The best way to protect your investment is by choosing the proper sealer for the area and type of stone you have installed. The best way to protect natural stone is by applying a sealer every year or two.
Oil-based: Oil-based sealers last longer, but they have a strong smell and may leave a sticky residue behind. Penetrating: Penetrating sealer seeps into the granite's pores to protect it from the inside out. Water-based: This type of sealer evaporates faster than other granite sealers and doesn't have a strong odor.
Countertops need to be resealed every year, depending on how much you use them. If you'd prefer to leave the task to the pros, expect to pay between $170 to $350.
You don't want to apply sealant too often. If you do, sealant will pool on the surface instead of absorbing into the stone. This will create a dull surface coating that makes your countertop less attractive. The surface coating is easier to damage than the granite, so you might notice scratches and burns.
Clorox and Lysol sprays and wipes are convenient, but they are not safe for granite countertops. They rarely contain bleach, but they do generally contain citric acid to help remove soap scum. Avoid using bleach as well.
Granite is Heat Resistant
Placing a hot pan on a well-maintained granite slab will not cause it to crack or weaken. Just remember that repeatedly placing a very hot pan on the same spot may cause granite to discolor.
It's important to understand that an impregnating sealer should not alter the color or finish of the granite counter. It won't make a polished surface dull, or a matte counter shiny. It's invisible when dry.
Resealing granite prevents permanent damage to the stone and restores the original, factory shine. There are many sealers to choose from, but your granite countertops retailer should recommend the best product for your exact variety of stone.
Frequent use of vinegar, Windex or bleach will dull the granite and weaken the sealant. Instead, a little soap and water should do the trick. Add dish soap and warm water to a sponge, get a good lather and begin cleaning. Avoid using abrasive pads, as granite can be scratched.
Sealing is a simple process. First, thoroughly clean the countertop surface with water and ph-neutral dish detergent, rinse with clean water and dry. As a final step it's a good idea to use a cloth saturated with denatured alcohol (available in the paint department) to do a final wipe down.