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Specialty Tools of the Hardscape Trade
Best Practices, Step By Step


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A wide variety of hand tools and machines, specifically designed for hardscape installations, can help in all phases of the process. And many can be used for different types of jobs, be the end product a segmental paver surface, concrete or asphalt pavement, retaining wall and other installations.


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According to Sean O'Halloran of The Toro Company, to compact granular soils, plate compacters do the best job since they can reach 6,000 vibrations per minute, causing soil particles to fall into a stable position beneath the surface, thereby eliminating air pockets. Plate compactors are available in forward-only, and forward/reverse models, which, by changing direction, makes concentrating compaction in one area more feasible. www.toro.com/en/professional-contractor/compactors


Hardscape installations generally have the same steps involved. The Interlocking Concrete Paver Institute describes the main ones as job planning, layout, excavating and compacting the soil subgrade, applying geotextiles if designated, spreading and compacting the sub-base and/or base aggregates, placing and screeding the bedding sand, and placing and finishing the final product. These usually also apply to concrete and asphalt pavement installations, and the construction of walls, columns, steps and the like.

Regardless the job, there are many tools available to simplify the work and improve the quality and accuracy of it. Those include of course traditional hand tools such as hammers, chisels, mallets, shovels, rakes, brooms, wheelbarrows, levels, measuring tools, tampers and more.

And then there are the traditional machines - tractors, loaders, excavators, and their attachments, that assist in everything from excavation, to transportation of materials, to the installation of them. But there also are more specialty tools, and following are best practices, step by step, when using these pieces of equipment.



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Besides packing down soil and crushed aggregate, vibratory plate compactors are used to seat pavers into the bedding layer. Characteristics to compare when purchasing or renting them include:
- Overall weight
- Horsepower
- Plate width and length
- Centrifugal force generated (in lbs.)
- Frequency (in vibration per minute or VPM)
- Working speed (in ft/min)

Many special features are available such as hardened steel plates, shock absorbing isolators, base plates with tapered bottoms and tapered or curved edges, handles with vibration damping, and mounted wheels for ease of transport.
www.pavetool.com/collections/weber-compaction-equipment


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O'Halloran says that rammers should be used to compact clay soil because their amplitude, the maximum movement of a vibrating body from its axis in one direction, is higher than plate compactors, and they can generally cover more ground in a shorter amount of time, can be handled by one worker, transported easily and they are able to fit in tighter areas than a plate compactor or trench roller. www.toro.com/en/professional-contractor/compactors


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Guidelines from the National Concrete Masonry Association say that within three feet of the front of the wall face, compaction should be handled by lightweight, low-energy, hand-operated equipment, preferably a vibrating plate compactor, which should be operated parallel to the face of the wall, passing closest to the wall first. www.ncma-br.org/pdfs/masterlibrary/TR146A%20SRW%20Inst.pdf


Initial Prep To ensure a solid foundation with which to build on, one of the first steps in hardscape construction is to compact the soil, which increases the density of a dirt bed, making it a more stable base. Soil type - whether cohesive (clay) or granular (sand, gravel and silt) - and soil moisture should be identified to help determine what piece of equipment to use.

For granular soils, plate compacters work best, according to Sean O'Halloran of The Toro Company, because they cause soil particles to fall into a stable position beneath the surface, eliminating air pockets.

In clay soil, rammers are recommended over plate compactors because their amplitude is higher. Rammers have lower vibration frequency but can generally cover more ground in a shorter amount of time. They provide hundreds of blows per minute and exert thousands of pounds of force, but only require one operator and are transported easily.

O'Halloran says that even though plate compactors are slower when compared to rammers, their added weight and larger surface areas can produce results that are smoother.



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Screeding sand, chip and rock can be accomplished by machines such as this one; touting potential production rates of 50,000 sq ft/day. Materials are loaded into its hopper, metered out constantly through two chutes, then screeded to the proper elevation - controlled by sonic, slope and/or laser sensors. www.probst-handling.com/products/29/64.html


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Construction Complete, a specialty online supplier of construction equipment, states that brick saws can cut to a depth of up to 3.75" with a 10" blade. The larger block saws (14" to 36" blades) can also be used in cutting granite or bluestone rocks. Some of the saws have fully-integrated dust collection as this iQ model does. Or you can add on dust removal devices like the Saw Muzzle from Dust Collection Products, LLC (inset). www.pavetool.com/collections/iq-power-tools www.dustmuzzle.com/home.php


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To help maneuver large pavers and wall stones, there are a variety of lifting devices that can be suspended from the arm of an excavator or boom equipped skid steer. Some manufacturers make them for specific products. Others are universal such as the Quick-E-Large Slab from Pave Tool Innovators that adjusts from 17" - 43" and holds up to 480 lbs. www.pavetool.com/collections/paver-installation-tools/products/quick-e-large-slab


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These paver lifters rely on a vacuum to lift and place pavers up to 50 lbs. The recommended safe lifting height is no more than 3" to 5" above the work area. www.paverplacer.com


Base Installation Trade association guidelines for various types of hardscape installations include recommendations on the use of tools and equipment. For instance, when preparing the No. 2 sub-base and the No. 57 base layer for a permeable paver installation, the ICPI advises to make at least two passes per lift with a smooth single or dual drum, minimum 10 t vibratory roller in the vibratory mode then at least two in the static mode until there is no visible movement of the stone - being careful not to crush the aggregate with the roller.

If an area cannot accommodate a roller vibratory compactor, ICPI acknowledges that a vibratory plate compactor with a minimum 13,500 lbf can be used.

For base preparation for retaining walls, the National Concrete Masonry Association advises that if compaction is not performed by a vibrating plate compactor with a minimum weight of 250 lbs., lift heights might have to be smaller in order to ensure the specified densities.

Other NCMA recommendations include that testing of the compacted fill must be carried out at regular intervals to check that project requirements are being met.

As for preparation of bedding layers, ICPI instructions for a permeable installation calls for spreading and screeding the material (No. 8 stone), then filling the voids left by removed screed rails. Vehicular and pedestrian traffic should be kept off the bedding material prior to the start of paving unit installation.

In regards to preparing a bedding layer of sand, an equipment division manager for a hardscape tool manufacturer states that screeding this course "continues to lead the list of most inefficient tasks for most paving contractors. Even some commercial projects, where the contractor is utilizing mechanized paver installers, are screeded the good 'ol fashion way: that is on hands and knees with a wood board."

He concedes that there will always be cases where some short board work is warranted, but advises to otherwise use specialty screeding tools.

When building walls with geosynthetic reinforcement, the NCMA recommends that tracked construction equipment not be operated directly on the material until at least six inches of backfill is installed on top of it. Sudden braking should be avoided, and turning "should be kept to a minimum to prevent displacing the units or fill and damaging the geosynthetic reinforcement."



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With a universal mounting plate for attaching to most skid steer models, and operating off the host machine's hydraulics, this vacuum lifting system has a lift capacity of 2,700 lbs. It is also compatible with small excavators, backhoes and cranes. www.vacuworx.com/products/sl


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ICPI guidelines state that a roller attachment on a plate compactor is essential for protecting paving slabs during compaction. www.icpi.org/paving-systems/paving-slabs/installation


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Mechanized paver installers can lift and place multiple paving units at once. This hydraulic installation clamp, which fits most excavators, can handle up to 800 lbs. per load. www.probst-handling.com/no_cache/products/29/62.html


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3D concrete placement through the use of GPS positioning systems that control screeding machines can help improve accuracy, volume production and labor costs, according to the manufacturers of those respective technologies. www.ligchine.com/gps


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Another option for 3D machine control, and a less expensive one, is to use a local positioning system (LPS). With it, a tracking station registers and maintains screed position by receiving and transmitting data to and from a tracker mounted on the screed machine. www.ligchine.com/3dlps-system


Putting Down the Final Layer Pavers often need to be cut to fit and the ICPI suggests doing so with a double blade paver splitter or masonry saw, typically with a 10-inch diamond blade, according to Construction Complete, an online retailer and wholesaler of construction equipment.

The blades for concrete block saws range from 14 inches to 36 inches and these saws can also cut large granite or bluestone rocks.

Another way to cut blocks, as well as masonry and concrete itself is with concrete cutters. They are designed for deep cutting, and cutting square corners, curbs and expansion joints. Their abrasive wheels' bond hardness affects the wheels' cutting life.

To help in the installation of pavers and blocks, a wide variety of mechanized and non-mechanized tools are available such as clamps with handles to help transport them. To help place them, there are lifting devices, some with vacuum assist, that can be operated by one person or two, lifting devices that connect to a backhoe's or excavator's boom, loader attachments with vacuum assist that can lift units that weigh over a ton, machines that install multiple units at once, and other clever innovations.

To vibrate concrete pavers into a sand bed, ICPI guidelines call for the use of a low-amplitude plate compactor capable of at least a minimum of 4,000 lbf at a frequency of 75 to 100 Hz.

For permeable pavers, they recommend at least two passes with a low-amplitude, 75-90 Hz plate compactor capable of at least 5,000 lbf. Do not compact within six feet of the unrestrained edges of the paving units.

For concrete installation, GPS positioning systems used to control dozers, motor graders, excavators and more can be combined with screeding machines to create 3D screeding. Ligchine International™ states that the GPS machine control from Topcon that their machines use can simultaneously run a fleet of earth moving machines and concrete screeding machines from a single GPS base station, and includes the ability to verify work, ensuring accurate jobsite specifications are met.

A less expensive option in 3D machine control is a local positioning system (LPS) that uses an automatic tracking robotic station to register and maintain screed position from a machine mounted prism and sonic tracker that transmits height adjustments to and from the screed machine via radio signal to maintain planned jobsite accuracy.

Some final equipment recommendations include one from the ICPI to keep skid steer and forklift equipment off newly laid pavers that have not received initial compaction and joint sand, and one from the NCMA to keep heavy construction equipment at least five feet behind the face of a finished retaining wall.

Without much doubt, hardscape installation will continue to be an extensive and lucrative segment of the landscape industry, aided by increasingly innovative tools. In the future, these look to include more use of robotics, 3D printing and...

Time will tell.




A Hardscape Business Add-on
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Laying curb, or as The Concrete Edge, manufacturer of the Lil' Bubba curb machines terms it, "turning mud into art, foot by foot," is a hardscape specialty business that they state is growing to meet the increased demand for it by customers. They market their products to experienced landscape professionals, but also to entrepreneurs, who may be interested in the low start-up costs and short learning curve. There are residential and commercial applications for the product, and besides decorative concrete curbing, their machine can also create walkways. A profit calculator is available at www.lilbubba.com/curbing-business.



As seen in LC/DBM magazine, October 2017.






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