ratio of hardcore to concrete Post your questions and get answers regarding all areas of drives, pathways and patios

[austind]

I'm looking to lay a slab of concrete up to 9 inches thick for a summer house, can someone let me know what depth the hardcore/scalpings needs to be under this layer. The thickness of the concrete is determined by a raised patio onto which the summer house doors open.

Thanks

[welsh brickie]

for a concrete base that thick, you will need reinforcing mesh to stop it from cracking, not a lot of hardcore is required unless the ground is constantly wet, 50mm thick will do, but it must be well compacted, so hire a plate compactor for the job.

[austind]

Thanks. Reinforcing mesh is on my list of materials and I have a whacker lined up too.