Staging of material
Most paver projects will vary depending on access, site conditions, project size and of course, the weather. These situations can have an overall impact on your project from a timing stand point. Careful consideration should be taken to determine the time to start the paver installation. Always try to minimize or avoid any traffic on the prepared areas.
The foreman or project manager should always have the materials (sand / pavers) distributed around the project site for easy and efficient installations. Paver pallets/bundles should be placed in a manner not to interfere with the paver installation. The proper pallet/bundle placement can make the actual project installation easier and quicker by reducing the overall labor of handling the material.
Brick paver patterns
Pavers can be placed in many different patterns depending on their shape. Each paver shape will generally have several different hatch patterns that are provided by the manufacturer.
The laying pattern and shape of the paver is very critical to the performance of the application. Contractors need to take into consideration the traffic weight loads on their paver projects. 90 or 45 degree herringbone patterns are recommended in all street and driveway applications, as these patterns will provide the maximum load support needed and will resist creeping from the turning of tires and starting or braking of vehicular traffic. In most applications worldwide, it has been shown that pavers laid in a herringbone pattern have performed adequately.
Pavers that are 60 mm (2 – 3/8 in) thickness are suitable for pedestrian applications. Pavers that are going to be used in commercial or industrial applications should be 80 mm (3 – 1/8 in) in thickness.
Reference/starting point for brick paver installation
There are a number of conditions that determine the starting point of a paver project.
When starting to install pavers it is best to snap a true straight chalk line on the surface of the bedding sand or pull a true straight string line above the surface of the bedding sand at the finished elevation of the pavers. This will help as a guide for maintaining straight joint lines and will also allow the installer to make adjustments in the alignment of the pavers.
Buildings and concrete curbing are generally not straight and should not be used for establishing straight joint lines. The use of string lines is essential to determine the true straightness of the edge as well. As the paver installation progresses, the string lines will help minimize the need for small trim pieces.
Joint width between pavers should be between 1/16 and 3/16 in (2 and 5 mm). There are some pavers with spacer bars on their sides. These will maintain a minimum joint width and allow the bedding and jointing sand to enter between each paver. Pavers with spacer bars are generally not laid in snug against each other since a string line will provide consistent joint spacing.
Installation of brick pavers
One of the most widely used methods for the installation of pavers is hand installation of each paver. It is best to install a single row of pavers along one of the true straight lines that you have pulled or above the bedding sand. This will give you a straight and true line off which to work. Once this row is established, you can continue to work outward into the field with the rest of the pavers. Always make sure to periodically check your joint lines to make sure they are true and straight. If not, adjustments to the pavers can be made as you continue installing. Pavers should be installed hand tight. The best method is to place a paver against another one and let it slide down into the bedding sand. Do not kick or tap the pavers into place as this can throw your lines out of true straightness.
When installing pavers on a steep grade, they should be installed at the base of the grade going uphill. This will prevent the pavers from creeping as they are being laid.
On large commercial and industrial applications, hand laying pavers would not be cost effective due to the labor intensity. The best way for installing pavers on large projects is to install them mechanically. The use of a mechanical laying machine can install approximately 6000 – 7000 sq ft a day. There are a couple items a contractor should consider before installing pavers mechanically:
- Mechanical installers are only capable of installing pavers in certain patterns.
- The contractor must make sure that the manufacturer is capable of manufacturing and bundling pavers in the desired pattern on the pallets for easy mechanical installation.
- Contractors may encounter a color blending situation coming off the bundles of pavers. Poor color blending could result in a patchy looking installation. Most manufacturers are consistent with color blending on each bundle of pavers, but it is the contractor’s responsibility to ensure proper blending in the field.
Cutting procedures for brick pavers
Contractors typically have two ways of cutting pavers. Pavers are cut either by 1). A double bladed guillotine or by 2). A gas powered cut off saw or brick saw which is equipped with a diamond blade. The diamond blade cut-off saw or brick saw will provide a much cleaner and more accurate cut. Most brick saws will have a hose attachment on them which will allow the operator to cut the pavers wet. When cutting pavers wet, it will help minimize dust and will prolong the diamond blades life as well. The operator of the brick saw should always cut the pavers away from the surface of the paver field when cutting wet, due to the fact that the pavers will create a slurry that will stain the paver surface. Pavers that are cut should not fit tight, sufficient spacing should be available for jointing sand.
The brick saw operator should always wear the proper protection that is needed for operating a saw, such as eye, ear, respiratory and hand protection.
Edge restraints play a major role in the overall success of an interlocking pavement installation. Edging restraints eliminate lateral movement of the pavers and hold the pavers tightly together. Especially at the outer perimeter of the paver application, without an edging restraint, your project is guaranteed to fail over time.
There are several different edging restraints from which contractors can choose. Typically manufactured edge restraints are the most commonly used by contractors. Manufactured edging restraints can range from, plastic edging, steel and aluminum, timbers or precast concrete and stone. An edging type that is used primarily in commercial and industrial applications is poured-in-place concrete curbs. This edging restraint is typically installed by other contractors.
When installing your edge restraint, it should rest directly on top of the compacted gravel base. The compacted gravel base course should extend a minimum of 6in beyond the perimeter of the pavers. This will provide a proper foundation upon which the edging restraint can sit. Manufactured edging (i.E. Plastic, steel or aluminum) should be firmly anchored into the compacted gravel base( check with the manufacturer’s literature for the recommended spacing of the spikes). There are some edging restraints that will extend deeper into the gravel base or beyond the base course (i.E. Timbers or poured-in-place curbs). Edging restraints should never be placed directly on top of the bedding sand. This could result in the migration of the bedding sand and eventual lateral movement of the pavers. If there is a possibility of losing bedding sand between the pavers and the edge restraint, then geo textile fabric is recommended. When a gap between the pavers and the edging exceeds 3/8″ (10mm), then the space should be filled with cut pavers. All edging applications should be properly back filled after they are installed to help provide additional stability.
Compaction of brick pavers
After installation, the pavers need to be compacted. The entire area that is to be compacted should be swept clean of any foreign objects and debris that can cause scratching or scuffing on the surface of the pavers.
It is important to have a compactor that can exert between 3000lbs. And 5000 lbs. Of centrifugal compaction force. In addition, it is important that the first compaction takes place before any jointing sand has been applied to the pavers. If jointing sand is applied to the pavers before compaction takes place, this can cause a bridging problem and will not allow the joints to be completely filled with jointing sand. This can also prevent the pavers from being properly set into the bedding sand.
When compacting the pavers, it is recommended that you make at least two passes in different directions across the pavers. This will allow the pavers to be properly set in the bedding sand and will force the bedding sand up into the joints from the bottom of the pavers.
The compaction of the pavers is very critical to the final performance of the pavers. Failure to do proper compaction can result in deformations and pavement failure over time.