Yes! Pavers can be laid directly over the top of the concrete. It’s a typical procedure and an excellent method for improving the quality of our concrete floors. The concrete condition, however, makes this a horrible idea. The best material for a paver base is crushed stone.
Although mortar aids in the installation of pavers, they can be set in place without mortar. It does, however, place us at risk of cracking and drainage woes.
While there are several paver bases, not all of them are ideal and some are more ideal when blended with other bases, such as sand and crushed stone. Let’s look at concrete as a paver base, other paver base options, which is best, and how to install them.
Is Putting Pavers Over Concrete Okay?
We can, but there are certain precautionary measures to take. Sometimes positioning pavers over concrete isn’t ideal. Our walking path or driveway can prove perilous, and if a surface isn’t in great form, it’s best to remove concrete.
Large cracks or a lack of a smooth surface will hamper your efforts to install paver tiles. The worse shape your space is in, the higher the tiles will need to be placed, which could block doors or cause people to trip.
Also, if the foundation is the problem and it continues to settle, it will damage the pavers you installed and force you to replace them.
How Do I Install Pavers Over Concrete?
- Inspect for Drainage Issues
Ensure that the area you plan to cover has a sufficient slope for water to drain away. If it isn’t, water that passes through the pavers will be unable to reach the ground due to the existing concrete, leading to drainage problems and standing water in undesirable areas. Drill drainage holes a few inches apart if it’s not sloped appropriately.
- Wash the Area Thoroughly
Clean the concrete slab in advance of laying the paver tiles by blasting it with water under high pressure. It’s best to let the area dry completely before laying the pavers.
- Sprinkle Sand Over the Existent Concrete
Coarse sand, at a depth of half an inch to an inch, should be spread over the existing concrete. Your pavers will have a solid base to stand on.
- Place The Pavers
The concrete is ready for the pavers to be laid on top. Put them together precisely, and then use the remaining sand to fill in the cracks.
- Use Edging or Mortar to Secure the Border
If you want your pavers to stay put, you’ll need to secure the edges. We can use mortar or other types of adhesive to keep them in place, or you can use a plastic edging tool.
What’s Best Under Pavers?
The convenience and ease of using sand as a paver base make it a popular choice. On the other hand, sand is not the best foundational material. When a foundation is built on shifting sand, the result can be a surface that is not level. You can tell if your foundation isn’t quite flat because of the unevenness in your pavers.
To strengthen the durability of crushed stone, sand is frequently added to the mix. Not all sand is suitable for use as a paver basis due to the wide range of fineness and coarseness available. The ideal base sand for pavers is washed concrete sand, according to the Interlocking Concrete Pavement Institute.
Bedding sand, sometimes called concrete sand, is gritty and doesn’t keep water from evaporating from under the pavers. Because of this, pavers can drain water after a downpour and keep their shape over time.
Crushed stone paver bases are constructed from uniformly sized stone fragments that have been shattered and sieved. Limestone, dolomite, granite, and trap rock are only a few of the many types of rocks used to make crushed stone, as reported by the Minerals Education Coalition. There are many different sizes of stone aggregate available, but 3/4-inch gravel is what most professionals recommend for paver bases.
Crushed stone, which facilitates water drainage and is easy to work with, is an excellent paver base material. Crushed stone, like sand, comes in many different kinds. Dense-grade aggregate extracted from quarries is ideal for use as paver bases. After being broken down at a quarry, stones are crushed to a size of 3/4 inches and then ground down further to produce stone dust. One of the greatest materials for maximum strength and cohesion, this blend binds effectively and boosts durability.
Concrete Aggregate, Recycled
There are environmental advantages to using recycled concrete aggregate (RCA) instead of traditional crushed stone. Crushed stone begins its life as “virgin aggregate,” which is mined and then extracted. Gravel from demolished concrete is used to create RCA.
When compared to the traditional method of extracting aggregate from the earth, the RCA process is a more environmentally friendly choice due to its lower carbon footprint and lower energy requirements.
Although RCA serves the same purpose as crushed stone in a paver base, we can’t determine its composition with any degree of certainty. Because of this uncertainty, the crushed stone may be a better option for a base material than RCA. Discuss the quality of the materials with your supplier if you’re considering an RCA paver base for your project.
Stone dust, often known as stone powder, is a fine powder made from finely powdered stones. Though stone dust can be useful when combined with other materials, experts advise against using it alone as a foundation.
An example of a substance with an abundance of dust particles is ” screening,” also known as stone dust. The particles act like a sponge, absorbing water and preventing the bottom layer from draining properly.
Experts claim that this water accumulation reduces the bearing and spreading capacities of a base. Choose a more sturdy base material to keep your pavers in place and secure.
Densely Packed Earth/Compact Soil
Typically, compacted earth is used as the subgrade level beneath paving stones. Although it is possible to put pavers directly on top of compacted dirt, doing so can lead to problems like:
Lack of drainage: compacted soil is not always the worst soil. When pavers are left wet for too long or if there is too much moisture, they become unstable and uneven.
Initial Unevenness: You may have trouble getting a perfectly even surface with compacted dirt alone, depending on where your pavers are placed. Without a subbase or base level, the pavers would be negatively affected by even minor hills and valleys.
For example, if the ground beneath your pavers freezes in the winter and thaws at different rates, your pavers may bend and sink. The pavers will reflect any change in the earth, making the path hazardous.
Installing pavers into other materials over compacted soil is preferable for security and uniformity.
What are Examples Of Good Practice For A Paver Base?
Selecting a suitable material for the paver base is only one part of laying a solid foundation. The efficiency and durability of a paved area depend on the quality of the paver base. Taking your time is probably the most useful piece of advice for building a solid foundation.
It might seem counterproductive to put in so much time and effort preparing three base layers before laying pavers. The time and care you put into ensuring that your base layers are of the right thickness, density, and consistency will be well worth it.
With the right foundation, your pavers can continue to look great and perform well for up to twenty-five years. Base construction is not something to rush if you want to achieve spectacular results. Considering your attention to detail, here are some general guidelines to follow when laying pavers.
How do I Ensure that the Paver Base is Properly Set?
Get Started With Excavation
A few inches of digging are needed for the paver foundation. Make sure you won’t strike any pipes, wires, or other utilities when excavating. To schedule an assessment two or three days ahead of time, dial 811 to be connected to your state’s phone center.
Utilities indicated that you can begin digging a foundation. There are two goals for this excavation. It removes excess dirt and creates a bed for the pavers to rest in.
Vibrating plate compactors are essential for ensuring the safety of your subgrade soil. Loose soil and subgrade soil must be compacted before laying pavers, and the area must be cleared of any debris such as grass, roots, large rocks, or leaves. This provides a flat foundation for further construction.
The Proper Depth of Subgrade and Slope
Subgrades made from granular soils are durable and well-drained, but those made from clay soils are not. Subgrade thicknesses of seven inches for granular soil and nine inches for clay soil are therefore suggested by the Interlocking Concrete Pavement Institute. The stability of your foundation depends on your ability to match the depth of your excavation with the depth of your soil.
Combine Crushed Stone with Sand
Using a sub-base of crushed stone that has been processed at a quarry and a base of washed concrete sand will ensure the finest possible paver installation. When combined with sand, the stability of crushed stone provides a workable, long-lasting base.
Pack Your Subbase Down In Stages
When constructing a subbase, it is best to lay down thin layers of crushed stone, compact them, and grade them downward. Your foundation’s strength will improve after compacting, and its ability to drain water will be preserved by grading it.
Get the Sub Base Level and Accurate
Subbase thickness is determined by the type of subgrade soil you are covering and the anticipated traffic loads of your paving stones. Clay soil needs a stronger subbase than granular soil would because it is weaker.
Absolute Evenness at the Bottom
Aim for a thickness of fewer than 1.5 inches when laying your concrete sand base. After the sand is spread, it must be leveled using a screed. The sand base can be made uniformly with the use of a variety of instruments.
Quick Paving Installation
After the base has been screeded, the pavers should be laid down carefully but rapidly. Leaving your base exposed to the elements overnight raises the possibility that it will be damaged by the wind, falling debris, or passing foot traffic. If you don’t act soon, you could end up losing more than just your foundation.