Coming home to a sunken spot in your block paving can be a shock; you might be worried about replacing your whole private driveway or shelling out for a professional to relay the sunken area.
In this guide, we’ll show you how to repair sunken block paving
Thankfully, this job isn’t as complicated as it might seem, and with the right tools and knowledge, you can repair any uneven area of your block paving yourself. Follow our handy guide below and you’ll be fixing your sunken block paving in no time!
Let’s get stuck in.
Why Has My Block Paving Sunk?
Loss of jointing sand
We’ve found the main reason for uneven block paving is the loss of jointing sand between the blocks. Because block paving relies on the friction of the sand to keep its structure, losing too much will cause the surface to sink. All block paved driveways will eventually lose some sand from weathering, cleaning or everyday use, but you can protect against this by re-sanding the joints around once a year.
Heavy vehicles
Regular use of heavy vehicles on block paving will, over time, result in uneven areas. Though a well-laid block paving driveway (with a solid sub-base material and laying course) can support a large amount of weight, regular use of heavy vehicles on the surface will put a strain on the joints and cause the paving to lose shape.
Was your drive laid properly?
If your block paving has been installed correctly, there shouldn’t be much risk of sinking. But, if the installed sub-base and laying course are made from the wrong materials, or the jointing sand hasn’t been properly compacted, you might begin to find low spots that result in uneven paving.
How to Lift, Relay, and Repair Sunken Block Paving
Required tools for this project
- Screed pipe
- Paving blocks
- Grit sand
- Trowel
- Hand brush
- Rubber mallet
- Kiln-dried sand
- Stiff broom
Step 1: Remove the Sunken Pavers
The first (and most difficult!) job when re-laying sunken paving is to remove the paving bricks that you want to re-lay. The key here is to remove enough joint sand around the blocks to allow them to be lifted away with ease.
Use a screed pipe to locate the low spots and mark out the area. It’s often quite hard to remove the blocks without damaging them, so you may have to use a brick hammer to break up the sunken blocks. However, once you’ve extracted the first block, the remaining blocks are often easy to pull out whole.
Ensure you have a few extra blocks for re-laying later, and remove the broken paving blocks from the laying course material. You might look into using a block extractor tool for this job, but they can be expensive to buy and, if you follow this guide, you shouldn’t need to use a block extractor tool more than once!
Step 2: Use a Screed Pipe To Correct Levels
Now the paving bricks have been removed from the low spot; you’re ready to use your screed pipe to correct the level of your paving. Place your screed pipe flush with the top of the sand base, making sure the pipe is level with the rest of the driveway. You may have to cut pieces to size to fill the gap in your paving, but make sure they are straight and level with the edges of your pavers.
Step 3: Add Grit Sand and Level It
With your screed pipe in place, it’s time to add a new bed of sand to the uneven area. At this stage, we recommend you investigate the cause of the low spot in your driveway. If the site is suffering from poor drainage, you might want to contact a professional.
When replacing the sand bed, always use grit sand, as grit sand will support your paving appropriately and provide far better drainage than building sand if your paving becomes wet.
Pour the grit sand into the low spot and run a level over your screed pipe to remove any excess sand. This will act as your new laying course. You can use a trowel to level off the bedding sand; make sure that the new sand is level with the existing bed.
Step 4: Relay the Blocks
With the area now level, here’s how to relay block paving. First, make sure that the blocks to be re-laid are clean, dry and free of any excess sand. Use a soft hand brush to remove any debris and lay the new blocks tight to the remaining paving bricks. Following the original pattern of your driveway, make sure that the relaid blocks are spaced out evenly between the joints.
We recommend that you work from the outside of the area, inwards, along the pattern of the paving to keep the paving close to each joint. After you lift and replace a few blocks, you may find it necessary to use a rubber mallet to tap the pavers into place gently; just be careful not to damage the blocks.
With the last few blocks, the space might be a little tight, so take care when you lift and place the pavers and use your mallet to tap them into position gently. You can use a vibrating plate compactor (or whacker plate) to produce an even finish, but this is completely optional.
Step 5: Re-sand the Area Repaired
Now that you’ve re-laid your paving bricks, you can re-sand the block paving and finish the job. When re-sanding block paving, always use kiln dried sand and only work when the area is completely dry.
Clear the area of small stones and organic material and apply dry sand to the joints in your paving. Make sure that all the areas that need re-sanding are covered, then use a stiff broom to work the fresh sand into each joint of your block paving. Take the time to ensure that the sand is adequately compacted into the joints, and sweep any remaining sand away. You should now be left with freshly re jointed paving.
Popular How-To Videos
You might find these video guides helpful if you’re a more visual learner.
How To Prevent Sinking in the Future
Now you know how to relay block paving; you might like to know how to prevent any future sinking in your patio or driveway.
We’ve found using a polyurethane sealer to set joint sand and strengthen the seal of your paving, works wonders at fixing any future issues and leaves your driveway or patio feeling like solid ground.
Here are the sealers to use on block paving.
Conclusion
So that’s how to relay block paving! We hope this information has been helpful and that these tips can help you re-lay your driveway, patio or any different area with ease. Check out our other DIY guides to produce impressive results with any landscaping job.