How to lay concrete paving
How to lay concrete paving
A step by step guide
Ensure you are wearing appropriate safety protection throughout your task. Wet mortar can burn exposed skin so make sure you are wearing suitable protective gloves and long sleeves to protect your arms.
This is a simple guide to laying a patio. We highly recommend consulting with a Bradstone Assured member for a professional installation.
Ensure you read our advice before beginning work on your new design project - this will mean you are fully prepared and have everything to hand, ready to complete your perfect garden...
Tools you need
Steel Toe capped safety boots
Before you begin
Always dry lay your patio first. This is a simple job of laying out the paving as you want the finished patio to be. Check the size, layout and, more importantly, that you have enough pavers.
Please note that sand type and quality varies across the UK and Bradstone concrete paving is best laid using coarse, sharp or concreting sand.
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!
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