Need Advice For Laying Flagstones Please

[needawin]

Wanting to lay flagstones where I have lifted turf. Area is 11 feet X 7 feet. Ground where I have lifted turf us pretty solid.
What sort of base do I need to prepare.
Mortar base only or hardcore. Or both!
What quantity would I need if mortar and similarly for hardcore.

[dustypuss]

HTH
http://www.blackmountainquarries.co.uk/articles/laying-flagstones/

[The Builder]

The important thing to remember with laying any type of oversite, is to make sure there is nothing "deleterious" under it. That is, anything likely to rot away. Vegetation; weeds; topsoil.

There's no single rule for this. The area may have been a veg plot where the soil is particularly rich.

In most cases though, just strip off the turf, and a few inches of topsoil. You just have to use your judgement. If the topsoil goes on forever, then you may decide to lay 100-150mm of hardcore and simply ram it well in. (40mm scalpings are ideal, but they may have a different name in your area.)

That's the sub-base in Dusty's link. For the bed, it says 5-10mm. I don't think that's practicable bedding. 25-40mm of plain sand would be easier to work with.

Although traffic will be light, the weight of the flags alone will cause them to sink if not on a solid base.

What does it look like under the turf?

[The Builder]

Ah ............. just read the link again...........

I see their bed is sand & cement. Use that instead of plain sand by all means, but 15-20mm is much easier. 5-10mm is rather thin unless on smooth concrete.

[needawin]

Many thanks both.