Before I get into technique again, lol, let me first recommend that you get in touch with your local paver dealers(assuming you're using concrete pavers) and investigate thier recommendations. I've hardly seen the same sealer twice in my travels. There are many different brands of sealers and three different types, generally. They are no/low gloss, medium gloss and gloss/high gloss. I've always directed my clients towards low gloss sealers for a couple of reasons. Primarily, penetration. Low gloss sealers tend to be thinner in consistency, which translates into deeper penetration. Secondly, aesthetics. Let me explain the benefits of each. The entire theory behind sealing concrete pavers is built around preservation. Sealing preserves coloration by preventing discoloration by things such as the sun and dripping fluids, mainly oils. I have never been a fan of the wet look. It looks completely unnatural to have a walkway that looks wet when it hasn't rained in days. With these factors in mind, it is my recommendation that pavers be sealed with a low gloss, deep penetrating sealer. This brings out the deep, rich, color without creating an artificial look.
First of all, the best time to seal pavers is in the dry season. You can start the process the same day it last rained if you wish. But the forecast for the next several days should be warm and sunny. Efflorescence is the risk you take when you apply a sealer to a moisture ridden pavement. It is the result of trapping(sealing) water in the pavement.
The first step in sealing pavers is cleaning. For best results, you'll need to rent a pressure cleaner. Use low pressure while cleaning the pavement. Pressure can be adjusted by adjusting the throttle. Ideally, 1500-2000psi will be used. Don't try to "power" out an oil stain. You'll most likely discolor the brick by exposing more of it's aggregate. If there is a stain that won't come clean enough by using low pressure, try dish soap or a paver cleaner with a scrub brush.
While cleaning the pavers you'll also be trying to wash the first half inch or so of sand out of the joints. This removes any debris or plant life. Be carefull not to wash the joints out to the surface of the sublayers.
Once you have cleaned the pavers, continue to use your rented power washer to clean the rest of your house, because you're not going to seal those pavers today. If your pavers were installed over a free draining base consisting of either crushed stone or a sand material, then you've only got wait a few days to allow for maximum drying, five if you're a perfectionist. You're welcome to use the pavement in the meantime. Just be sure to shut down those particular irrigation zones.
If your pavers are installed over concrete, or a clay-based material like road gravel or diamond dust, then you'd better wait a few extra days. Clay holds water much longer than sand does. And you don't want your hard work to go to waste.
Now that you've had ample drying time, it's time to finish the project. The first thing you'll need to do is replenish the missing sand. I recommend that you use kiln dried bag sand like baby sand or play sand. Like the sand in an hourglass, it will work its way through the smallest crevices. Leave a dusting of sand on the entire project.
Next you'll need to either rent or borrow a plate compactor. Compact the entire surface of the pavement(unless your pavers are installed on a concrete base) on high speed. This does two things. It levels any inconsistencies that may have developed and it vibrates the sand tightly into the joints. Once you've compacted the surface, use a blower on it's lowest speed to clean the dust from the pavement and blow the surface sand into the nearest joint. Keep the end of the blower at least seven feet from the point of impact so that you don't blow the fresh, loose sand away.
Once you've successfully dusted the pavement, it's time to seal it. There are two popular ways to apply a sealer. Sprayers and rollers. Rollers are generally used with high gloss sealers since the consistency of the sealer is thicker. But we're not using high gloss sealers so let's get a cheap sprayer from Ace hardware. Cheap because the sealant will surely be a match for the components of the sprayer.
Start against a wall and work your way away from where you start. Its best to use a piece of cardboard along edges. It helps if you have a helping hand. Apply the sealer generously. Low gloss sealers dry pretty fast in warm weather. A good coat insures that the sealer penetrates before it drys. Don't slack off between refills or you'll be running to the hardware for another sprayer. Your pavement will most likely be ready for foot traffic within an hour and vehicle traffic in less than 24 hours. If you've followed these steps you should expect to repeat this process in no less than three years, perhaps as many as six.
Not only have you preserved your pavers, but you've done a little preventive maintenance on the joints. By using fresh, dry sand in the joints you've given the sealer something to soak into and bond. This creates a grout effect which aids in the prevention of plant intrusion and insect manifestation. Congratulations.
I hope this helps you and others out. If you have any questions you're welcome to ask.
Professional Landscaping Companies, LLC
Traverse City, Michigan
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