How to design a durable, low-maintenance clay brick paver system:

Acme Brick Clay Pavers

Firstly, there are two different typical installation methods. Your pavers can be installed on a flexible base system or a rigid base system. A flexible base system tends to necessitate the fewest repairs over the life-cycle due to the simple fact that it is flexible. Everyone knows that when the forces of the earth want to move something, it WILL move. The flexible base system allows for this to happen without major damage and a proper design will keep this movement from becoming a physical hazard. A rigid base system has its purposes as well. If you want the look of mortar joints between your pavers, a rigid base is necessary. It is very common to apply brick pavers over existing concrete that is in good condition, it is usually not feasible to remove the concrete just for the sake of having a flexible base. In areas of extreme safety importance such as steps, a rigid base with mortared joints may be more appropriate. However, bear in mind that the rigid base is a point of possible failure which would require possibly expensive repair somewhere down the line. This being said, the peace of mind regarding safety will usually outweigh the increased potential maintenance costs for a limited area of the pavement.

It all starts at the base

If a flexible base is used, the proper selection of the base, or foundation, is critical. Industry standards call for a minimum of 4" of aggregate, graded from 3/4" down to fines. While every supplier will have a different label on their aggregate, one particular name for this is 21AC Natural Sand and Gravel. Care should be taken to select an aggregate that will not introduce soluble salts into the system as this will lead to efflorescence. If the composition of the aggregate is such that there are voids not filled with fines after compaction, a fabric or Geotextile should be used to separate the aggregate from the bedding sand which will be placed above.

The bedding sand should be well graded angular sand that will allow for adequate drainage. Again, different labeling may apply and the most common is 2NS or sharp sand.

Keeping it together

The next most important consideration is the edge restraints. The edge restraints provide one of three forms of interlock between the paver bricks. Without all three forms of interlock in place, your pavers will move than intended and may crack, chip, or even crumble apart. Many types of restraints are used the goal is to make your restraints as solid as possible. You could purchase plastic or steel strips which get spiked down into the base, or you could bury the outside row of bricks upright into the ground and trowel cement up against them. (Be sure to use a bond breaker to allow for differential movement.) An existing structure such as a home's foundation or a poured cement driveway could also be used.

Respect your paver's personal space

The next item for consideration is the sand you will sweep between the joints of the brick pavers which is also the third dimension of interlock. Sadly, this is also one of the most common errors in installation. As the flexible base below moves or when a load is applied to a paver, it will want to twist. Because the outside of the pavement is held in place with your edge restraints, whatever is next to the paver will prevent the twisting. If the paver is installed tight to another paver, they fight. One of them will lose and you are left with a chip on the surface. Because sweeping sand is softer than the pavers, the proper width of a sand joint will prevent this chippage. Some pavers come with narrow spacing bars to ensure the proper joint width, which is approximately 3/16".

You want to be sure that the sand you select is fine enough that it will completely fill the voids between the paver bricks. The joint sand is the most common maintenance issue with a clay brick paver system. While the cost of this maintenance is relatively low, it can be avoided altogether by using polymeric sweeping sand. This sand will bond together preventing sand loss due to wind, rain, etc. An added bonus is that polymeric sand virtually eliminates weed growth and insect infestation. It is quite low in cost compared to the benefits it provides.

Keep it looking good

Sealing your genuine clay pavers is not necessary. Because the clay is vitrified in a kiln at extreme temperatures, you do not need to do anything else to them to protect them from the elements. The surface will not wear away and the color is not affected by ultraviolet light.

Cleaning your clay pavers manually is usually not necessary as nature typically keeps them looking great. However, there are some exceptions. If your pavement, or areas of it, will be subject to high moisture and low sunlight, (Think of a paver sidewalk alongside watered bushes.) moss will be inevitable. Depending on the surroundings and your taste, this new characteristic of your pavement may be a welcomed enhancement. However, if your design is more on the contemporary side, you should look for ways to reduce the moss-inducing factors or plan regular cleaning as part of your maintenance program. If you are using brick pavers for a driveway, there is the potential of vehicle fluids leaking onto them. These can be cleaned either with a mild detergent or a cleaner designed specifically for this purpose. For stubborn stains, most real clay pavers can be simply extracted, turned over and re-installed.

Tags: clay pavers