How To Clean Pavers Before Sealing. You’ll also want to make sure that you get any sand joints and weeds blasted so that the area is completely clean. Dirt and stains aren’t the only things that can affect the appearance of pavers over time;
You don’t want to seal dirt, grime, or mildew into your bricks. When combined with water the sand and polymers mix creating a strong bond and locking the pavers in place. If your power washer is unable to remove those difficult stains, you may need to use some basic cleaning solutions.
Driveways & pavement concrete that has been weathered for years may already have the shiny top layer removed naturally and all it needs is a good clean with a water jet to prepare it.
This will give your pavers a sand finished look that will last. You can power wash the pavers, as long as there isn't sand in between that would be washed away. Efflorescence cleaning is a critical step when sealing pavers. Concrete pavers are made from a concrete mixture of small aggregates all the way down to fines.