How To Lay Paving Slabs On Sand (Guide)

Creating a patio on sand is a popular and cost-effective way to add functional outdoor living space to your home. While it is a relatively simple process, it is important to approach the task with the right tools and materials, and to be aware of the limitations of this approach.

In this article, we will guide you through the steps of laying a patio on sand, and explain why this is not a good long-term solution.

Tools and Materials

Before you begin, it's important to make sure you have the right tools and materials for the job. Here is a list of what you will need:

Paving slabs: Choose patio slabs that are thick enough to withstand foot traffic and outdoor use. It's a good idea to purchase a few extra slabs in case any break or crack during installation. Sharp sand: You will need enough sharp sand to create a base layer for your patio. As a guide, you will needs a thickness of around 30-50mm. MOT Type 1 sub base: A 100mm compacted layer of MOT Type 1 beneath the sand can help to improve drainage and prevent the sand from washing away over time. Shovel and rake: These tools will be used to level the sand and create a smooth surface for your slabs. Plate compactor or garden roller: A plate compactor or garden roller is used to compact the MOT Type 1 and sharp sand and create a stable base for your slabs. Spirit level: A spirit level will help you to ensure that your patio is level and even. Rubber mallet: A rubber mallet can be used to tap the slabs into place and ensure they are level.

Steps to Follow

Step 1: Prepare the Area The first step in laying a patio on sand is to prepare the area. This involves removing any grass, plants, or debris from the site, and excavating the soil to a depth of around 150-200mm. Once you have excavated the area, add a layer of MOT Type 1 to the bottom of the hole. This will help to improve drainage and prevent the sand from washing away over time. Lay in two courses of 50mm each and compact down between layers.  Step 2: Add the Sand Once you have added the MOT Type 1, it's time to add the sharp or grit sand. Begin by pouring a layer of sand onto the MOT Type 1, and use a rake to spread it evenly across the surface. The sand should be around 50mm deep. Next, use a plate compactor or roller to compact the sand and create a stable base for your slabs. Work the compactor or roller over the surface of the sand in a back and forth motion, starting at the edge of the patio and working your way inward. Once the sand has been compacted, use a spirit level to ensure that the surface is level and even, although remember to ensure there is a slight slope away from your home to allow rainwater to run away. If you notice any high or low spots, use a shovel to adjust the sand accordingly. Step 3: Lay the Slabs With the sand in place, it's time to lay the paving slabs. Begin at one edge of the patio, and work your way across the surface, placing each slab in the desired location. Use a rubber mallet to tap the slabs into place and ensure they are level with one another. It's important to leave a gap of around 1-2cm between each slab to allow for expansion and contraction due to changes in temperature and moisture. Also, some paving may have tolerances on the dimensions so it's good practice to dry lay some slabs first to get a feel for the spacing you need to follow. Remember to always mix packs of natural stone paving to ensure an even mix of colours. Step 4: Finishing Touches Once you have laid all of the slabs, it's time to add the finishing touches. This may involve adding sand to fill in any gaps between the slabs, or adding edging stones to create a neat and tidy border around the patio.

Why This is Not a Good Long-Term Solution

While creating a patio on sand can be a cost-effective and relatively easy way to add outdoor living space to your home, it is important to be aware of the limitations of this approach.

Historically, laying paving slabs on sand was a common practice, particularly in areas with sandy soil. This was because it was a relatively easy and cost-effective way to create a functional outdoor living space that was often installed for the practical hardstanding aspect rather than its aesthetic appeal.

Today, some people may still choose to lay paving slabs on sand for similar reasons. For example, if you are on a tight budget, creating a patio on sand can be a more affordable option than a full mortar bed installation. Additionally, if you have sandy soil on your property, using sand as a base for your patio can help to create a stable and level surface.

However, it is important to note that laying paving slabs on sand is not considered a best practice in the industry. This is because sand is not as stable or secure as a full mortar bed, and can lead to uneven surfaces, instability, and potential damage to the slabs over time.

The rationale for not installing paving on sand is as follows:

• Over time, the sand beneath the slabs can become compacted and settle, or even gradually erode away causing the slabs to become unsteady and potentially break. This can create an uneven surface and make it difficult to use the patio safely. It will also allow weeds to grow between the slabs.
• Additionally, while the layer of sand does provide some stability for the slabs, it is not as secure as a full mortar bed. This means that over time, the slabs may shift or move, creating an uneven surface that can be dangerous to walk on.
• Finally, while the sand layer does help to improve drainage, it is not as effective as a full mortar bed at preventing water from seeping beneath the slabs. This can cause the sand to wash away over time, leading to further instability and potential damage to the slabs.

For these reasons, creating a patio on sand is generally considered a temporary solution, and is not recommended for long-term use. Unfortunately, some "cowboy builders" may still use this approach as a shortcut to cut costs and time in the installation process. It is important to be cautious when hiring a contractor and to ensure that they are using proper installation methods and materials to ensure the longevity and safety of your patio. If you are looking to create a patio that will last for many years, it is recommended that you invest in a full mortar bed installation, which provides a more secure and stable base for your slabs.

Conclusion

Creating a patio on sand can be a cost-effective and relatively easy way to add functional outdoor living space to your home. However, it is important to approach the task with the right tools and materials, and to be aware of the limitations of this approach.

By following the steps outlined in this article, you can create a patio on sand that is stable and level, and that provides a comfortable and functional space for outdoor entertaining and relaxation. However, it is important to remember that this is a temporary solution, and that for long-term use, a full mortar bed installation is recommended.