"Adam-the-Kiwi" wrote:
Hi

I am looking to put down a new paved patio in my garden. This is
approx 12m2 and will only get light use. I have come across some
conflicting advice regarding what to use as a sub-base.

Some advise that for a low traffic area 50mm of sharp sand will
suffice.

Some advise that 75mm of foundation is required beneath the sand. Of
these some say to use aggregate alone, some say to use a mix of
aggregate and cement.

So my questions are, is an aggregate foundation necessary, and if so
should cement be included? Also, should the sharp sand be mixed with
cement?

Cheers, Adam

The only way of making sure that the slabs stay put is to lay them on a
mortar mix. Providing the ground under the mortar is firm you shouldn't need
hardcore for a light use patio area. But if the soil is soft then you
probably need a sub-base of compacted rubble.

http://www.homebase.co.uk/wcsstore/homebase/en_US/images/p0//HBHowToArticles/articles/howto_buildpatio.html
http://www.focusdiy.co.uk/stry/diy23&bklist=pcat,3,advicecentrecategory,diycatego ry

If you just lay them on sand then you may get tilting and rocking later.