How to Fix a Dip in a Sunken Bradstone Block Paving Driveway

Block paving is still the most used paving type in driveways but even though it is the best variety of paving for supporting the weight of cars, over time it can still sink and dips can form where forces are focused such as by the wheels of heavy cars. Bradstone block paving can sink because unlike larger format paving stones, the pavers actually float on a bed of compacted sharp sand. This is why block paving is so easy to lift up and replace making the it ideal for areas where access is needed for maintenance jobs such as drainage and cable laying. However as mentioned, the sharp sand can over time sink, particularly when disturbed or not compacted correctly and give your driveway block paving a tired, uncared for look.

However all hope is not lost for your paved area because just as block paving is easy to lay, it is also relatively easy to repair. The dips that form can be levelled in just a few hours by following this DIY guide with little equipment and very few materials required. All that you will need is a trowel or improvised straight edge, a small shovel, some extra sharp sand to refill the affected area, some kiln dried sand, and a rubber mallet. However if you’re carring out this work on a large area with multiple dips, it might be worth renting a compactor plate (otherwise known as a wacker plate) for the day or even just an hour or two if possible.

To start with, you’ll want to identify the areas that have dipped. For this it might be worth marking the area with chalk to make it easier to remember which pavers to pull out. Use a spirit level or straight edge to see where the dips occur and then pull out the pavers that are wonky and then the adjacent ones to those just to be sure that the dip doesn’t reoccur later.

Pry up the middle block paving piece with a trowel or even with two forks. A few gentle knocks with a hammer could help if it seems stuck. Getting the first block out can be a bit tricky but once you have the first one up the rest are easy. Once you have lifted all of the affected blocks, dig out the sharp sand below to a depth of at least 50mm or until you reach the base material which should be type 1 aggregate.

Replace the sharp sand along with the new sharp sand into the hole and level it with your trowel or straight edge. It should be loosely compacted and at a level so that the block paving pieces sit 10mm proud of the surrounding blocks. Once all the block pavers are replaced you can begin either hammering them down with your rubber mallet or going over them with your rented compactor plate. Through this vibrating action, the sharp sand below is bumped around and begins to interlock forming a denser and compacted bed for your block paving. Your replaced pavers should also now sit level with adjacent ones.

If they don’t become level no matter how much you try to push them down it means you had compacted the sharp sand too much while refilling and levelling the hole and you will have to start the process over. However as the materials in block paving are all dry and don’t go off such as is the case with a mortar or concrete bed meaning you can take as many tries as you like.¬†Once you’re happy with the levels of your relaid Bradstone block paving, scatter some kiln dried sand over the replaced blocks and sweep over them with a broom so that the sand fills in the gaps between the blocks.

Did you find this DIY guide helpful or do you have any other questions? If so please leave a comment below.


One Response to “How to Fix a Dip in a Sunken Bradstone Block Paving Driveway”

  1. Anonymous | March 26, 2014 at 17:57 #

    very helpful thanks….:-)

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