If you’re remodeling your kitchen or are building a home and have decided you want granite countertops, you may already know a little bit about sealing them. This stone is quite porous, which means that any liquids that come into contact with the stone will seep into it. This can result in stains you cannot remove and even odors being trapped within the stone. If you want granite countertops for your kitchen, it’s important that you understand why sealing countertops is important and how to go about doing it.
The Importance of Sealing a Granite Countertop
If you don’t seal your granite countertop, you’ll quickly see why you made a mistake. Spills, even if only a few drops hit the counter, can leave behind stains and other marks. Even if you quickly clean up the mess, you’re still likely to see stains due to how porous granite is. It only takes a second for the liquid to seep into the pores, and once it has, it’s incredibly difficult, if not impossible, to get the stain out. If you don’t seal the counters, your gorgeous granite could be ruined.
When you seal granite, the sealant you use actually seeps into the stone’s pores. This prevents other liquids from being able to enter those pores. Over time, though, the sealant does begin to break down. Because of this, it is important to reseal your granite countertop regularly.
What to Seal Granite Countertops With
The next question you may have about sealing granite countertops is what type of sealant to use. There are two options, water-based, and solvent-based products. Water-based sealing products are more environmentally friendly, while solvent-based sealants are able to more deeply penetrate the granite, allowing for a better protective barrier. Make certain the sealant was designed for natural stone counters, too.
Regardless of which type of sealant you use, you want to look for products that contain fluorocarbon aliphatic resin as the primary or active ingredient. This ingredient makes the sealers more expensive than those that use silicon or siloxane. However, it can provide protection for up to ten years, while other sealants may need to be reapplied as soon as six months if the counters are heavily used and around the three-year mark for low use.
Why should you invest in a product that contains fluorocarbon aliphatic resin? Most other ingredients used in sealants will only protect the granite against water. This special type of resin, however, also repels oil. For granite counters in the bathroom or other areas, this may not seem like a big deal—you typically don’t have oils there. However, granite in the kitchen may come into contact with salad dressings or cooking oils. If any of these products spill on your granite that has only been sealed against water, they can seep right through that seal and damage the stone.
Wondering how much sealant you need? In most cases, a quart will cover around 200 square foot of counter. For average kitchens, then, you’ll only need to buy one quart. If you have granite counters in your kitchen and bathroom(s), you may need two quarts to cover everything. Of course, always check the sealant you’re purchasing to see what the manufacturer suggests.
How to Seal a Granite Countertop
Now that you have your sealant, it’s time to apply it to your counters. The first thing you will want to do is find out if your countertop was pre-sealed. Some are, and if you just had the granite installed, it’s likely the contractors applied a layer of sealant. If you’re not sure, it’s always better to add a layer of sealant just to be safe. Your granite counters are beautiful, but they’re also costly to buy and install. You don’t want to have to go through that cost again to replace damaged granite. But how do you know when it’s time to apply a new layer of sealant?
The Water Test
The most reliable way of determining whether or not you need to seal a granite countertop is to do the water test. This test is very simple. First, pour out about a fourth of a cup of water onto your counter. Start a timer on your phone or other device as soon as you do. When all of the water has been absorbed, stop the timer. You can also do this test with oil, but make certain it’s not an oil that will stain. Also perform the test in an inconspicuous location such as a corner.
If you see that most or all of the water has not been absorbed, then your seal is still intact and doesn’t need to be replaced. However, if the counter has a noticeable dark spot where you poured the water, then some of it was absorbed into the stone. It will eventually evaporate, but in the meantime, you want to be very careful about future spills. The sealant on the counter has worn off, and you’ll need to replace it.
The Timer Results
Take a look at the timer on your phone. How long did it take for the water to be absorbed? This will help you determine how porous your granite is. If the water was absorbed almost instantly, it means your counter is very porous and will likely need to be sealed fairly often (annually in some cases). It also means you need to quickly clean up spills.
If it took up to five minutes for the water to be absorbed, it means you should reseal your counters every three or four years. You’ll want to redo the water test before you reseal just to make sure it’s necessary.
Finally, if it took over ten minutes, it shows that your counters are very well sealed. You will want to do the water test every year or if you see spills absorbing quickly, but there’s no need to worry about reapplying sealant right now.
Applying the Sealant
If the water test shows that you need to reseal your granite kitchen countertops and you’ve purchased a sealant, it’s time to apply it. Carefully read all of the instructions on the product, including all warnings. You will likely want to open the windows in or near the kitchen to help with the smell of the sealant, and you may need to close off the space to your children or pets so they don’t get into the product while it’s drying.
Next, clean the counters. You don’t want to seal any moisture, crumbs, or other debris inside. Don’t use any harsh cleaners on granite and avoid anything abrasive. Mild dish soap and warm water is a good option. Once you’ve wiped the counters down, use a soft cloth to dry them and then allow them to sit for up to 24 hours. This will ensure that any water that was absorbed into the granite’s porous has evaporated.
Next, apply the sealant in an even coat, and let it fully absorb into the granite. Usually this takes around 20 minutes., but again, refer to the instructions on the product. Apply a second and even a third coat after the previous coat has dried.
Once you’ve done the last coat and waited the indicated amount of time, use a soft cloth to wipe away any remaining sealant. You then need to leave the sealant to fully set. In most cases, this means you cannot use the counters for 48 hours, but refer to the specific instructions on the product you are using.
How Often Should You Seal Granite Countertops?
In most cases, you’ll need to reapply your sealant around every four years, but it truly depends on a number of factors. The first is how porous your slab is. As indicated above, the water test can help you determine this. The sealant you’re using is also a factor here. If you do apply a sealant that uses fluorocarbon aliphatic resin, you won’t need to reapply it quite as often.
The best way to tell if you need to consider resealing your counters is to do the water test once a year. You can mark this on your calendar, but you can also watch how any spilled water acts when it hits the counter. If you notice that water is being absorbed fairly quickly, you may want to do the proper test right away.
Should You Use Granite for Counters?
With all the need for resealing, some people do wonder if they should use granite at all. While granite does require this extra maintenance, it’s also a durable and beautiful option for your kitchen, bathroom, and other areas. Granite can give your kitchen a homey, warm feel, or it can make the space feel open, sleek, and clean. It all depends on the color and veining in the stone you select. If you’re willing to take the time to reapply sealant as needed, granite is a great option.