What base under pavers?

[dweller]

I am looking at paving beside my house. I understand the 100mm crushed road base compacted however if I have a clay base around my house does the road base need to be as thick or can I use the clay and road base to make the 100mm ie 20mm clay base and 80mm road base?

The reason I ask is that with a solid clay base, digging it out could be difficult. Don't mind the work, but if I don't need to dig it out, I won't.

thanks for any advice.

[JacobZ · Accepted solution]

Hi @dweller,

Thank you for your question about creating a compacted base for pavers.

80mm of road base should be fine considering the clay is already hard and compacted, but if you experience heavy, consistent rains in your area, you should definitely consider going deeper.

In a compacted base for pavers, the road base serves two purposes, the first being its ability for compaction and levelling to allow a flat, solid surface for the pavers to be laid on.

The second, which will be far more important in your situation, is its ability for water to move through it while still maintaining its compaction and solidity. Clay, while compact and solid, does not allow for draining in the same way as road base will. You will find that the less road base you use, the more likely you are to have water pooling around your pavers causing movement in the pavers.

Ultimately the thickness of your paver base is your choice, but a bit of extra work now might save you from a lot of work later to fix things that have been shifted around by water.

You might like to have a look through How To Prepare And Lay a Base For Pavers for some guidance on base preparation.

Let me know if you have any questions.

Jacob