Crushed stone makes a solid paver base because it allows water drainage and is easy to work with. Like sand, crushed stone comes in several varieties. The best aggregate for paver bases is a quarry processed dense grade aggregate. Quarry processing creates a combination of 3/4-inch crushed stone and stone dust.
The paver bed is usually made of sand, 1/4″-10 crushed gravel, or synthetic material, and is the topmost paver support layer keeping pavers in place.
Sand Bedding
Before laying the pavers, a layer of bedding sand is placed over the compacted base material. This layer provides a bed into which the pavers are set.
To achieve a firm base from the beginning, you need to make sure you have the correct depth of sand under pavers. We recommend allowing for a depth of at least 30mm loose sand. This will pack down to about 20-25mm depending on the method you use for packing and will allow for drainage without your pavers shifting.
A GRAVEL BASE LAYER BEFORE SAND IS A MUST! Using sand alone to set pavers is not enough. The best and recommended paver base is 3/8-inch crushed gravel. The gravel provides a flexible base that absorbs ground tension to prevent frost heaves.
Dry laying allows porcelain pavers to be laid directly on grass and sand, but also on gravel, thanks to their reduced thickness of 20 millimeters that avoids the use of adhesives.
Paver sand holds the pavers in place and allows you to adjust them. The final paver sand depth needs to be 1 inch and you need to account for sand filtering into the paver base and into the joints between the pavers.
The guidelines are 4 to 6 inches for pedestrian walkways and 8 to 12 inches for driveways. Local soil conditions also impact depth needs. Generally, clay bases need to be dug deeper to facilitate drainage. Consult your local dealer for further guidance.
Without sand, the pavers are likely to shift and sink over time, resulting in an uneven and messy surface. The sand keeps the pavers in place, preventing unnecessary replacements and repairs, as well as keeping your patio free from tripping hazards.
After you lay gravel, you'll need to spread a smooth layer of concrete sand for your pavers to settle in and stay. If you try to replace either of these aggregates with dirt, it won't be long before you have to tear it all up and start from scratch.
Prepare Ground
Ensure you have a root and rubble free compatible sand sub-base of at least 50mm thick. The sub-base should be roughly levelled and damped down before tamping down firmly with a hand or mechanical compactor. Hand compaction is usually enough for most domestic applications when laying pavers.
Concrete sand is the proper sand for laying a foundational base for a concrete paver installation. It is extremely coarse sand so it can be compacted uniformly and allows for adequate water drainage. Concrete sand will lift slightly into the joints of the pavers when they are being leveled, locking them into place.
Why You Need Drainage Under Pavers. Water can be a home's worst enemy. A build-up of moisture around your home can damage your foundation and your landscaping, cause mold and mildew, put you, your family, and your pets at risk of slipping and falling, and much more.
Whilst it is technically possible to lay pavers on bare, unprepared ground, this practice is not recommended as the ground will shift over time, causing the pavers to develop a sunken look, or even crack.
To provide the very best ground reinforcement, it can be infilled with aggregate, pea gravel, sand, or stones in areas with heavy foot or even vehicle traffic.
A sand paver base is one of the most popular options due to sand's accessibility and spreadability. However, sand is not an ideal base on its own. Over time, sand shifts and can create an uneven foundation. If your foundation is anything but level, your pavers will show it.
Polymeric sand is the more reliable and durable option for filling in the paver gaps. It outperforms regular sand when a homeowner is looking to lock the paver joints properly and wants a steady and stable path. It also provides a better appearance with its cleaner look and availability in varied colors.
You'll be using 4 inches of gravel, which is 1/3 of a yard, for a paver base. To figure out how many cubic feet of gravel you will need, multiply your square footage by 1/3. In this example, you'd need about 20 cubic feet of gravel, or 3/4 cubic yards. You may want more in case you spill some.
If you want your pavers to last, then you need to ensure that they have a strong foundation. You might have seen cracked or uneven pavers. They are a result of a poorly installed paver base. So in short, installing a paver base is crucial to get an even, flat surface that is easy to walk on and will last for years.
MJS Materials writes that typically paver sand is called leveling, all-purpose, or paving sand. It's made up of coarse grains and SF Gate writes that it's a preferable material for creating the thick bedding that you lay your pavers on top of.
Polymeric sand can withstand extreme weather conditions and is highly resistant to erosion. Aside from holding the paver joints, polymeric sand also prevents water from seeping through it. This significantly reduces the risk of cracking and shifting from your pavers.