I taking up an old patio and relaying with sandstone.
I had planned to lay 100 mm type 1 then lay the slabs on 40mm mortar bed.
The old patio was laid on dry cement biscuit mix which is crumbly in some places but very hard in others.
The height of the new patio will allow for about 50 mm of type 1 on top of the previous sub base. It is a solid base and it seems pointless digging it up just to relay with new type 1. Is it ok just to top up with type 1 to the right level.
Also, where I am digging up the looser sub base, it is very dry, crumbly material that looks like dirty sand (picture attached). Can this be re-used it should I bin it if there is fine dirt mixed in? It compacts well under foot and I will hire a compactor to do it properly.
I had planned to lay 100 mm type 1 then lay the slabs on 40mm mortar bed.
The old patio was laid on dry cement biscuit mix which is crumbly in some places but very hard in others.
The height of the new patio will allow for about 50 mm of type 1 on top of the previous sub base. It is a solid base and it seems pointless digging it up just to relay with new type 1. Is it ok just to top up with type 1 to the right level.
Also, where I am digging up the looser sub base, it is very dry, crumbly material that looks like dirty sand (picture attached). Can this be re-used it should I bin it if there is fine dirt mixed in? It compacts well under foot and I will hire a compactor to do it properly.