Masonry Magazine October 2010 Page. 22
PAVERS
Recommend a plate compactor to complete your equipment short list to go into segmental paving. You can rent one first to determine which one meets your needs.
Check with the local technical or vocational school to see if they offer segmental pavement training within an existing masonry or landscaping program. Consider hiring a recent graduate. Or, look into an apprenticeship or other hands-on training for yourself or your employees. For example, the School For Advanced Segmental Training (www.paverschool.com) does an excellent job, as do many of the Interlocking Concrete Pavement Institute programs. Trade shows and manufacturers are other excellent resources. Hardscape North America is in Louisville, Ky, this month, Oct. 28-30. Many courses are available for attendees (www.HardscapeNA.com).
How about a quick run-through?
* Determine the laying pattern. Herringbone is best for vehicular applications.
* Excavate a minimum of 12 inches for vehicular traffic, eight inches for pedestrian. Some projects require an engineer to determine base thickness.
* Proper compaction is essential to the life of an installation, both the sub grade and base layers. A 98 percent compaction is recommended.
* There are different methods of screeding sand.
* PaveTech's Sand Screed Pro could be a worthwhile investment to speed the process on larger installs. A simpler method, maybe to begin with, is to lay down two lengths of one-inch metal conduit, parallel to each other and several feet apart. Cover the pipes with concrete sand (ASTM C33), and then use a board across the top of the pipes to screed the sand level. Remove the pipes and use a trowel to fill and smooth the voids.
* Lay the pavers in place and install edge restraints.
Paver installation will challenge you, and it's a worthwhile challenge in a recession when business, municipal and residential projects favor remodeling, add-ons and makeovers, rather than new construction.
In addition to that, there's new demand and appeal for green construction, including permeable pavers for stormwater retention. Clay pavers are green before they arrive at a jobsite. They are made of the most abundant building material on earth (clay and water), they last virtually forever, and they can be recycled in countless ways.
Permeable clay pavers, like the StormPave and RainPave from Pine Hall Brick Co, are green twice. With a conventional concrete or asphalt surface, certain pollutants (antifreeze, road salts, motor oil, etc.) are washed across the surface after the first inch or so of rainfall, and are then washed into the nearest stream. A permeable surface means that the same water and pollutants will seep into the soil, where it will be naturally filtered.
The best part is that the demand for permeable pavers is growing. The recent survey by the American Society of Landscape Architects of its leading members showed that designs incorporating permeable paving systems that retain or detain stormwater on site are increasingly being specified by property owners and developers.
Using permeable clay pavers can help satisfy state and local stormwater management requirements by recharging the ground water, reducing runoff and, therefore, reducing the volume of stormwater discharge, which reduces erosion downstream. It also allows builders to potentially qualify for LEED credits in four ways, including stormwater design, heat island effect-non roof, use of recycled content and use of regional materials.
Permeable clay pavers appear virtually identical to conventional pavers, except that there's more of a void area between them. Even so, the void area is less than one-half inch, thus meeting Americans with Disabilities Act requirements for sidewalks.
A second difference can't be seen: Conventional pavers use a combination of crusher run gravel topped with sand; permeable pavers use open-graded aggregates without