In article ,
Dr Teeth wrote:
Just knocked down an old conservatory and the only remnants is a thick
concrete slab - just thought an easy solution would be to lay grass but
obviously not. I will think about a patio instead.

With a smooth surface like that, you can lay a patio on as little as
1" of sand, though using 2" is easier. That leads to a minimum total
increase in depth of 3".

You can also consider making raised beds or planters using bricks
or concrete blocks, which are very good for growing drought tolerant
plants in.


Regards,
Nick Maclaren,
University of Cambridge Computing Service,
New Museums Site, Pembroke Street, Cambridge CB2 3QH, England.
Email:
Tel.: +44 1223 334761 Fax: +44 1223 334679