Introduction
Indian sandstone is a highly sought-after choice for paving due to its versatility, wide range of colours and durability. Whether you are planning a new garden pathway or a patio, understanding how to lay Indian sandstone correctly is essential to ensure both the longevity and visual appeal of your outdoor space.
This practical guide walks through the main steps involved, from planning and preparation through to installation and finishing.
1. Setting Out
Before starting excavation or ordering materials, it is important to plan your project carefully. Visualise how you would like your patio or pathway to look and consider design features such as curved edges or brick borders.
Once the desired shape and dimensions are decided, mark the area using pegs or spray paint.
Calculate the square meterage of the area and add approximately 10% to allow for cuts and possible breakages.
2. Buying Your Paving
Selecting a reliable supplier is important when purchasing Indian sandstone paving. Quality paving stones and consistent processing help ensure the durability and appearance of the finished patio.
Lower-cost materials sourced from softer sandstone deposits can sometimes be more porous and may be more susceptible to staining or freeze-thaw damage. Choosing a reputable supplier can help reduce these risks.
Established brands such as Marshalls, Bradstone, Pavestone and Paving Slabs UK are commonly chosen for reliability and consistent product quality.
3. Working Out Your Levels
Setting the correct levels is important for both drainage and overall appearance. Establish your finished level using reference points such as house walls or existing paving.
Paving around a house should generally be approximately 150 mm below the damp proof course.
A tight string line between reference points can be used to guide excavation and level setting.
4. Drainage Planning
Effective drainage should always be considered when installing paving. Surface water should flow away from buildings and drain naturally from the paved area.
Indian sandstone is naturally more absorbent than some paving materials, which means poor drainage can lead to algae growth and slippery surfaces.
5. Excavation
The excavation depth is typically around 160 mm, allowing for:
20 mm paving thickness
40 mm mortar bed
100 mm sub-base
Ensure the excavation is neat and free of loose soil. Poor ground preparation may lead to settlement and cracked paving.
6. Sub-Base
A well-compacted sub-base is essential. MOT Type 1 aggregate is commonly used because its angular particles compact effectively.
Compact the material using a vibrating plate compactor until a solid and stable base is achieved.
7. Preparation
Before laying the paving, position the sandstone slabs close to the work area. If the patio uses multiple slab sizes, organise them by size to help maintain the intended pattern ratio.
Keep tools and materials organised and take care to avoid cement splashes that could stain the stone.
8. Mortar Mix
A common mortar mix used for laying Indian sandstone is:
1 part cement
4-5 parts sharp sand
Some installers also add a small amount of soft sand to improve workability.
9. Mortar Thickness
The mortar bed should generally be between 30 mm and 40 mm thick. Beds that are too thin may lead to weak support, while overly thick beds can be difficult to level.
10. Laying the First Slab
The first paving slabs set the levels and direction of the patio. Ensure the edges align squarely with walls or existing features.
Use a long spirit level to confirm the correct falls and ensure the slab is fully supported by mortar.
11. Maintaining Joint Consistency
Indian sandstone often has a naturally rustic finish, which means slab sizes may vary slightly. Maintaining consistent joint widths therefore requires careful placement.
Typical joint widths for sandstone paving are around 10 mm.
12. Keeping Your Lines Straight
Use string lines and straight reference edges such as walls to maintain straight lines while laying slabs.
Check alignment regularly as you progress across the patio.
13. Managing Long Joints
When laying mixed-size patio packs, avoid creating long continuous joints. These should be interrupted by other slabs to maintain the correct laying pattern.
14. Keeping the Project Clean
Cement and mortar stains can permanently mark sandstone surfaces. Keep water and a brush nearby to clean any splashes immediately.
15. Grouting
A typical pointing mix is:
1 part cement
3 parts plastering sand
The mixture should be slightly damp, similar to brown sugar, to allow precise pointing without staining the slabs.
16. Sealing (Optional)
Indian sandstone is naturally porous. Sealers can help reduce staining from substances such as oil, wine or bird droppings.
Sealing is optional but may help preserve the appearance of the paving.
Conclusion
Laying Indian sandstone paving requires careful preparation, correct materials and attention to detail. Following these steps can help achieve a long-lasting and attractive patio.
We aim to provide customers with practical information on laying patio paving slabs. Many helpful installation guides and videos are also available online.
When installing patio paving, it is important that mortar is applied evenly across the base to form a full mortar bed.
Slabs should always be laid on a full mortar bed. Spot bedding methods such as dots or rings should be avoided, as these can lead to instability and water staining.
Natural stone contains pores that allow moisture absorption. Proper installation helps minimise the risk of water staining.
If customers wish to reduce the risk further, a suitable sealant may be applied after installation. However, no sealant can guarantee complete stain prevention.
Frequently Asked Questions
How deep should I excavate for Indian sandstone paving?
A typical excavation depth is around 160 mm, allowing for the paving slab, mortar bed and sub-base.
What mortar mix should I use for Indian sandstone paving?
A common mortar mix is 1 part cement to 4 to 5 parts sharp sand, with enough moisture to achieve proper adhesion.
Should Indian sandstone be laid on a full bed of mortar?
Yes. Indian sandstone should be laid on a full mortar bed rather than on dots and dabs, as this provides better support and reduces the risk of movement and water staining.
How wide should the joints be for Indian sandstone paving?
As a general guide, joint widths are often around 10 mm, although slight variation may be needed because sandstone is a natural product.
Should I seal Indian sandstone after installation?
Sealing is optional, but it can help reduce the risk of staining and make maintenance easier.
Download Patio Laying Patterns
600 Series - 4 Size Patio Pack (18.90m2)
600 Series - 4 Size Patio Pack (15.30m2)
560 Series - 5 Size Patio Pack (15.76m2)
560 Series - 3 Size Patio Pack (19.30m2)
