A step by step GUIDE

Planning a DIY patio upgrade? Environmentally friendly natural stone paving is an attractive and lasting choice, and relatively easy to install. Whether you're opting for limestone, granite or Indian sandstone, follow this guide to laying natural stone paving for fantastic results.

 

Before you begin laying natural stone paving

Please note:

Before you start, ensure you can complete your patio by dry laying your natural stone paving. Arrange the slabs as you want them to lie on the finished patio, checking the size and layout and that you have sufficient pavers. 

Read this guide and related blogs to swot up on the process before you start. When you're laying natural stone paving we also recommend consulting a Bradstone Assured member for a professional installation.

Tools you need

You'll need simple equipment to lay your natural stone patio slabs:

  • shovel
  • Trowel
  • Rubber mallet
  • String line
  • Pegs
  • Spirit level
  • Steel Toe capped safety boots

 

Wearing appropriate safety protection is essential. Wet mortar can burn exposed skin so don suitable protective gloves and a long-sleeved top to protect your arms. We also recommend steel-toe cap boots to protect your feet when you're handling heavy slabs.

A step-by-step guide to laying natural stone patio slabs

 

STEP 1 MARKING OUT

Mark out the area, allowing an extra 150-300mm for working room.

STEP 2 EXCAVATION

Excavate a total depth of 150mm, allowing for a 100mm sub-base, a 30mm mortar bed and the paving itself. To comply with building regulations and protect your property from damp, the paving must also be at least 150mm below any damp-proof course (DPC).

STEP 3 ESTABLISHING LINES AND LEVELS

The paving needs a slope or fall of around 1:60, i.e. 17mm of fall for every metre width or length of the patio. Use one taut string line to guide alignment along the length of the paving, and a second along the breadth. When laying, you should use a straight edge and spirit level to repeatedly check that each new paving unit correlates to both lines, adjusting the height up or down to give the necessary fall.

STEP 4 SUB-BASE

A Type 1 or MOT sub-base is required to give strength and stability to your patio. It is good practice to use a geotextile over the ground first. Spread the aggregate out, forming an even layer below the string line. Use a plate compactor to consolidate the aggregate down.

STEP 5 BEDDING

Use a mechanical mixer to make a mortar of 4:1 sharp sand to Ordinary Portland Cement (OPC). Avoid building sand or white cement. The mortar should bind together without being sloppy or runny. A plasticiser can help get a more workable consistency.

STEP 6 PREPARING THE BED

Using your trowel spread the laying bed to cover the area where the paver is to be laid. The paving should sit approx. 5mm above the string line before being tapped into position. 

STEP 7 PRIMER

All paving should be primed with a polymer modified cementitious slurry primer to adhere the paving to the mortar bed. Use a masonry brush or trowel/float to coat the entire underside as per the manufacturer's instructions. Take care to avoid getting any primer on the face of the flags as it sets rock hard and can be impossible to remove if allowed to dry.

STEP 8 PLACING

Lower the paver onto the bed. Gently tap down the paver onto the bed using your rubber mallet. Adjustment will be necessary to ensure that the paver is fully supported and does not rock or move and you should use a straight edge with a spirit level repeatedly to check that each paver achieves the desired level and the fall as per the string line

It is good practice to immediately wipe down the paver using clean water and a sponge and it is essential that any Bradbond slurry primer that may have accidentally found itself on the face of the paver be removed immediately. You will not be able to remove this once it has set.

Remember to clear enough mortar from the gaps between the pavers to allow sufficient jointing compound to sit comfortably. Check and follow the manufacturers' installation instructions if you are using a jointing compound to check the application and suitability. A dry application method must not be used on heavily textured paving such as Mahina, Textured, Stonemaster or Natural Granite as it is prone to staining when jointing compound has not been fully worked into the joints. 

If cutting is required a suitable specification of blade is required along with a water input for dust suppression. It's important that all the relevant PPE is worn during this stage.

Lastly, dress the patio…and enjoy!

STEP 9 CLEAN AND CLEAR

It's good practice to immediately wipe down the paving slab using clean water and a sponge, looking out for any slurry primer that may have fallen onto the face. This should be removed immediately as it won't come off once set. 

Remember to clear enough mortar from the gaps between the pavers to allow sufficient jointing compound to sit comfortably. Follow the manufacturer's installation instructions to check the application and suitability. A dry application method must not be used when laying heavily textured natural stone paving as it is prone to staining.

If cutting is required, you'll need a suitable specification of blade along with a water input for dust suppression. You must wear all relevant PPE during this stage.

Lastly, dress the patio… and enjoy!

Four tips for success

As a reminder, follow our four tips for success:

  • Always dry lay the patio first to ensure you have checked the measurements
  • Create a good solid foundation and check the depths
  • Start laying the patio from the corner and work outwards
  • Check the levels and fall frequently to make sure you stay on track

Explore further how to lay natural stone paving by checking our advice section. Here, you can get tips on laying different kinds of paving stones and more.