In article ,
Janet Baraclough writes:
| The message . com
| from "pookey" contains these words:
|
| at the moment i think removing the concrete, adding a layer of
| gravel/small stones (quary dust maybe)???? followed by some sand/grit
| and top soil with mixed sand sounds good with some drainage channels
| around the outside edge.
|
| Sorry, it doesn't sound too good.
|
| There are scores of different sands, gravels, grits dusts, etc. It's
| essential to install the right material at the correct depth, for the
| situation, local rainfall, subsoil, water table etc. Otherwise, it can
| be an expensive and fruitless waste of labour, materials and money.

You are making this out to be far harder than it is. Grass grows on
pretty well ANY substrate in the UK, and dunes turn rapidly into turf
if they don't dry out too badly.

Quarry dust might compact and clog, but all that is needed for a substrate
is to be about the right size (hence free-draining but small enough to
stop too much sand/soil falling though until the grass roots bind them)
and non-toxic to grass. Pretty well ANY gravel will fit the bill, as
will a lot of other materials.

Exactly how much drainage is needed for a lawn is a trickier question,
but 150 square metres isn't a huge area. From the posting, the subsoil
can be assumed to be nearly impervious, but a 6" fall (i.e. thickness of
gravel) in 12 metres is over 1% - masses. The real point is that you
(a) don't want it clogging and (b) don't want it to dry out too fast.

| The best advice you got in this thread was Rupert's recommendation.
| The Pavingexpert really is an expert in that field, he is an ex-urgler
| and gives clear, comprehensible, accurate advice free.

That page is good, but it is almost certainly overkill for this case.
As his related pages were with my paths/patio.


Regards,
Nick Maclaren.