DIY Sub Base for Paving Slabs

Creating a DIY sub base for paving slabs is an essential step in ensuring a stable and long-lasting patio or pathway. To start, grab a trusty spade and dig out the selected area to a depth of approximately 6 inches (150mm), making sure to level the ground as you go. Once the area is cleared, it's time to lay down the road base or hardcore material. Aim for a compacted depth of 2 inches (50mm) and ensure it’s evenly spread across the entire area. Once this is done, repeat the process to create a sub base that measures 4 inches (100mm) in total. Next, it's crucial to add a layer of sharp sand on top of the sub base. This layer of sharp sand will provide additional stability and help with leveling the patio slabs. Finally, it's time to lay the paving slabs themselves. Arrange them in the desired pattern, ensuring they’re evenly spaced with a small gap between each one. This gap will allow for drainage and allow for slight movement as the ground shifts over time. By following these steps and taking the time to create a solid sub base, you can ensure that your new patio or pathway will stand the test of time and provide a sturdy surface for years to come.

What Is the Best Sub-Base for Paving Slabs?

Sand blinding is often used when the ground is already relatively stable and just needs a smooth surface to lay the paving slabs on. It isn’t as strong or as durable as hardcore, so it’s generally not recommended for areas with heavy traffic or where there’s a lot of weight being placed on the slabs.

When selecting a sub-base for your paving slabs, it’s important to consider the type and size of the slabs, as well as the intended use of the area. If you’re installing large, heavy slabs or if the area will be subjected to heavy traffic, it’s best to opt for a more robust sub-base like hardcore. This will provide the necessary stability and prevent the slabs from sinking or shifting over time.

To create a DIY sub-base for paving slabs, start by excavating the area to the desired depth. This will depend on the thickness of the slabs and any additional layers you plan to add. Once the area is excavated, it’s important to ensure that the ground is level and well compacted. This can be done using a plate compactor or by manually tamping the soil.

Next, add a layer of hardcore to the excavated area. This should be laid in even, compacted layers, with each layer being no more than 100mm thick. Use a compactor or a heavy roller to compact each layer before adding the next.

After the hardcore layer is in place, you can add a layer of sand blinding. This should be spread evenly over the compacted hardcore layer and should be approximately 50mm thick. Use a long, straight piece of timber to level the sand and create a smooth, even surface.

Finally, lay your paving slabs on top of the sand blinding, ensuring that they’re level and evenly spaced. Use a rubber mallet or a wooden block to tap the slabs into place, ensuring they’re firmly bedded. Once the slabs are all in place, brush a layer of jointing sand into the gaps between the slabs and then use a compactor to vibrate the slabs and settle the sand.

Alternative Sub-Base Materials for Paving Slabs

When it comes to creating a stable base for paving slabs, there are alternative materials that can be used as a sub-base. These materials can provide a strong foundation and help prevent shifting or sinking of the slabs over time.

One option is to use compacted gravel as a sub-base. Gravel is a relatively inexpensive material and can provide good drainage properties. It should be compacted in layers to ensure stability and prevent settling.

Another alternative is crushed stone or crushed rock. This material is often used in construction projects and can provide a solid base for paving slabs. Like gravel, it should be compacted to create a stable surface.

If you’re looking for an environmentally-friendly option, recycled crushed concrete can be used as a sub-base. This material is made by crushing and recycling old concrete, reducing waste and conserving natural resources.

It’s important to properly prepare the sub-base before laying the paving slabs to ensure long-term durability. This includes removing any existing vegetation, leveling the ground, and compacting the chosen material to create a solid foundation for your project.

When it comes to choosing a base for your pavers, professionals typically rely on three main options: sand-set, open-graded, and synthetic materials. Each of these base materials comes with it’s own set of benefits and drawbacks. In this article, we will explore each option in detail to help you make an informed decision for your upcoming paver project.

What Can I Use as a Base for Pavers?

When constructing a DIY sub base for paving slabs, there are several materials you can use as a base for pavers. Professionals typically use three main base materials: sand-set, open-graded, and synthetic. Each of these options comes with it’s own set of benefits and drawbacks, so it’s important to carefully consider which one is best for your specific project.

Sand-set paver bases are a popular choice for many DIY enthusiasts. This type of base is made up of compacted sand that provides a stable foundation for the pavers. It’s relatively easy to install and can be adjusted as needed during the installation process. However, sand-set bases may require frequent maintenance, as the sand can wash away over time, causing the pavers to become uneven.

Open-graded bases are another common option for DIY sub bases. This type of base is composed of crushed stone or gravel that’s compacted to provide a stable and permeable surface. Open-graded bases allow for better drainage, preventing water from pooling and causing damage to the pavers. However, they require careful installation to ensure proper compaction and stability.

Synthetic bases are a newer option that’s gained popularity in recent years. Synthetic bases offer excellent drainage and are resistant to erosion and shifting. They’re also relatively easy to install, as they can be cut to fit any shape or size.

When it comes to laying paving slabs, a crucial step is to create a solid foundation. One common method is to lay a concrete mix mortar bed that’s approximately 50mm deep. Once the mortar bed is prepared, carefully place the paving slabs on top and ensure they’re leveled and spaced correctly. After tamping them down, it’s important to allow 24 hours for the concrete mix to cure and set properly. This ensures a sturdy and durable base for your paving project.

What Do You Lay Under Paving Slabs?

When it comes to laying paving slabs, it’s important to ensure that you’ve a solid sub base to support them. One common method is to lay a concrete mix mortar bed, with a depth of around 50mm. This helps to provide a stable and level surface for the paving slabs to sit on.

To start, prepare the ground by clearing away any debris and ensuring it’s level. Then, mix the concrete according to the manufacturers instructions, making sure it’s a smooth and workable consistency. Spread the mortar bed evenly over the prepared area, using a trowel to smooth it out.

Once the mortar bed is in place, carefully lay the paving slabs on top, pressing them down firmly to ensure a good bond. It’s important to leave the desired joint spacing between the slabs to allow for expansion and contraction. Use a spirit level to ensure that the slabs are level and also sloping away from any buildings or structures to promote proper drainage.

After laying all the slabs, leave the set for at least 24 hours so that the concrete mix can cure. This curing process is important to allow the mortar bed to harden and provide a solid foundation for the paving slabs. During this time, it’s important to avoid walking or placing heavy loads on the newly laid slabs to prevent any damage.

Once the mortar bed has cured, you can then proceed with any additional finishing touches, such as sealing or grouting the joints between the slabs. This will help to enhance the durability and longevity of your paved area.

How to Create Patterns or Designs Using Different Types of Paving Slabs.

  • Choose the type and shape of paving slabs you want to use for your pattern or design.
  • Plan the layout of the pattern or design, considering factors such as the size of the area, available slabs, and desired aesthetic.
  • Prepare the area by removing any existing materials or vegetation, ensuring a level and stable foundation.
  • Lay the base layer, typically using crushed stone or gravel, and compact it to provide a solid and even surface.
  • Start laying the paving slabs according to your planned pattern or design, ensuring proper alignment and spacing between them.
  • Use a rubber mallet or a masonry hammer to firmly tap the slabs into place, ensuring they’re level and secure.
  • Continue laying the slabs, adjusting as needed to maintain the desired pattern or design.
  • Fill the gaps between the slabs with jointing sand or mortar, brushing it into the joints and compacting it for stability.
  • Clean the surface of the paving slabs, removing any excess sand or mortar, and ensure they’re free of debris or stains.
  • Consider applying a sealant or protective coating to enhance the appearance and durability of the paving slabs.
  • Maintain the pattern or design by regularly cleaning the surface, removing weeds or moss, and addressing any damage or issues promptly.

Crushed stone is an ideal choice for creating a solid base for paving projects. It offers effective water drainage and is convenient to handle. Additionally, various types of crushed stone are available, allowing you to choose the best fit for your needs. Among these, a quarry processed dense grade aggregate stands out as the top pick for paver bases, ensuring excellent stability and durability.

What Can I Use as a Base for Paving?

When it comes to creating a solid base for paving slabs, crushed stone is a popular choice among DIY enthusiasts. One of the main reasons for it’s popularity is that it allows for proper water drainage, preventing any potential pooling or flooding on the surface. Additionally, crushed stone is relatively easy to work with, making the installation process much more straightforward.

By properly grading and compacting the crushed stone, you can ensure that your pavers will sit evenly and securely, reducing the risk of movement or sinking over time. This stability is crucial in creating a durable and long-lasting paved area.

It can be used as a base for both mortar-based and sand-based installations, depending on your preference and the specific project requirements.

When selecting crushed stone, opt for a quarry processed dense grade aggregate to ensure optimal stability and a level surface for your paving project.

Different Types of Crushed Stone for Paving Bases: Explore the Various Options Available for Crushed Stone, Such as Limestone, Granite, or Gravel, and Discuss Their Specific Qualities and Benefits for Paving Projects.

When it comes to creating a sturdy base for your paving slabs, there are several types of crushed stone to consider. Each type offers it’s own unique qualities and benefits for your project.

Limestone is a popular choice for paving bases due to it’s durability and ability to compact well. It provides a strong foundation and helps to prevent shifting or settling of the paving slabs.

Granite is another excellent option, known for it’s strength and resilience. It’s highly resistant to weathering and can withstand heavy loads, making it ideal for areas with high foot traffic or vehicular use.

Gravel is a versatile choice that comes in various sizes and shapes. It allows for good drainage and is easy to install. However, because of it’s looser composition, it may require more maintenance over time.

Ultimately, the choice of crushed stone for your sub base will depend on factors such as your project requirements, budget, and personal preferences. Consulting with a professional or local supplier can help you determine the best option for your specific needs.

Source: Best Paver Base Material – Nitterhouse Masonry Products


By following the DIY steps, such as digging out the area, leveling it, and laying a compacted sub base of road base/hardcore, you ensure a sturdy foundation. Remember to leave a small gap between the slabs to allow for expansion and contraction. With the proper sub base, your paved patio won’t only look great but also withstand the test of time.

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