If you find an area that is experiencing this problem, you need to first determine the cause. If there is no edge restraint installed, you should consider installing some. Sometimes the edge restraints do not have enough spikes installed to hold the pressure exerted by the paving surface, in which case additional edge spikes need to be added. There are a number of great “invisible edge” restraints available that are easy to install and are just spiked down into the base materials. Be sure to lift any areas along the edge that need repair. Usually this is just a matter of a few stones along the perimeter. After the pavers are installed with the recommended gap size, install the edge restraint as per the manufacturer’s recommendations.

Two common mistakes are made with this repair:

• Often, the sides of the pavers are not cleaned before reinstalling. If you do not remove the sand or polymeric sand from the sides of the stones it will be very difficult to get them back into place properly, so I recommend you use a putty knife to clean the sides. If the joints were filled with polymeric sand, it is easier the clean it off if you wet it down. Most polymeric sands are designed to soften up when they are made wet, making removal easier.

• The second common mistake is not installing the edge restraint directly on the granular base. It is very important that the edge restraint is sitting directly on the compacted granular base, not the soft soils surrounding the project, as the spikes will not hold in the softer materials. This is one of the reasons it is always recommended that the base be extended past the paving surface edge. If you do not have a good base to spike the restraint to, you should do a little excavation and install a good stable base.

2. Inspect the surface for any deformations (dips): Deformations are usually caused by base or sub base settlement. New homes that have had a lot of property grading prior to the building of the home are more prone to this. As a rule, settlement usually shows up in the first couple of years after the project’s completion. Settlement should always be addressed, as it could cause some pooling of water. You have to identify the area that has been affected and mark with chalk. A good level or a straight edge placed on the surface will quickly reveal the area in need of repair. The hardest part of this job is getting the first stone out, if possible, try to start at an edge and work your way to the area. If this approach is not practical then you can try a couple of screwdrivers down either side of a stone to pry it up. I have found that blasting the sand out with a hose first makes this much easier. Always start with the smallest stone in the pattern, as it is easier to get them out. There are a number of stone pulling tools available but not all rental shops carry them, so be sure to phone ahead. After you get that first stone out, you can get under the other stones and the job becomes much easier. Once you have all of the stones removed, re-level the area with the appropriate amount of sand and reinstall the stones, taking care again to clean side of all the stones. You can tamp the stones with a block of wood placed on the surface and hitting with a hammer.

3. Inspect the surface for stains: You will be surprised what a good cleaning will do after a long winter to bring life back to your paving stones! If there are no serious stains to address, then a good pressure wash will do the job. If a pressure washer is not available, use a bit of dish detergent in some water and clean the area with a stiff bristle broom. Unilock’s HC Hardscape Cleaner works wonders at cleaning our products as well as a large variety of other concrete products. The most import tip to remember with any concrete cleaner is to always read the Instructions. There are right and wrong ways to use these products. The wrong way can diminish the effectiveness of the cleaner and in a worst case scenario, it can actually discolor the paver. I always recommend trying a cleaner in a small unobtrusive area to make sure you are happy with the results.

4. Consider Sealing: All of our products are designed to have long lasting, maintenance-free surfaces that do not need to be sealed, but if you chose to seal your product for color enhancement or stain protection, you will need to re-seal every 3-5 years. Site conditions can vary the time between applications; on heavy traffic areas such as driveways, you will have to re-seal more often but never apply sealer more frequently than 2 years. When selecting sealers, you can choose between a high gloss sealer, which will enhance the color of your paving stones or a matte finish that will protect the pavers. Unilock has a full selection of sealants for you to choose from. You must clean the pavers before applying any sealants, as this will ensure a better bond between the sealant and the surface of the product on a first time seal. If you are resealing, cleaning the pavers beforehand will ensure that ground in dirt does not get sealed in. Also, if you are re-sealing it is very important to use the same sealant as originally applied, there are a number of different sealants out there all having their own formulas. One of the critical components of re-sealing is that the new coat should dissolve the first coat and bond together to create a consistent surface protection. If you apply different sealers, you may not get this bonding action or you may have a chemical reaction that will turn the sealant milky. If you do not know what sealant has been applied previously then do a small test of an obscure area of pavers and see how the new sealer reacts. It is also critical that the surface be completely dry before applying any sealant, any water on the surface or in the joints can interfere with the bonding of the sealant to the surface of the stones.

5. Applying Joint Sand: If you have a paving surface that does not have polymeric sand in the joints, our Unicare Joint Stabilizing Sealer is the product for you. This sealant adds a protection to the paving surface as well as the joints where it will bond the sand together to resist joint sand erosion and weed growth. One common mistake I have seen with this product is not applying enough of the sealer to adequately saturate the joints. Remember, you are not just sealing the stones but you are trying to get the product into those joints.

Even with the advent of the polymeric sands and joint sealers, there are some weeds which can be persistent. You should always remove young seeding weeds immediately. Sometimes, it is just as simple as using a screwdriver or nail to dig down into the joints and remove the root system. I personally use a little vinegar mixed with dish detergent to create an environmentally friendly weed killer.

Following this little bit of preventative maintenance every year will protect your investment and keep it looking great for years!