[H]omer wrote in message
...
Hi folks,

I finally took the plunge and started digging to discover the cause of
my drainage problems. Surprise, surprise - it's heavily compacted soil
on top of solid clay ... lots of clay.

I haven't got the patience to wait for the effects of soil improvement
techniques, so I've decided to start from scratch and just excavate the
whole site.

What I need to know is this:

1) ... What depth should I dig to? (I have a digger).
2) ... What type of aggregate and organic materials do I need?
3) ... What depths should each material be, and in what order?

My best guess is (top to bottom):

Compost
Topsoil
Sharp sand
Chips (granite?)
Hardcore

Is this correct? What depths for each?

Is the materials and depths different for lawn areas than for borders?

I've already excavated a test area about 12'x3' and discovered all kinds
of builders rubbish, including massive lumps of concrete and plastic
bags, etc.

Both front and back gardens are flat; the back has full sun; the front
is shaded. I'm in the N/E coastal area of Scotland (clay country), and
it's wet and windy.

Thanks,

[H]omer

Hi Homer,

I wonder how deep you're excavating, and how close to your house. I must
assume that your house is built on the same heavy clay, and I am concerned
about subsidence if you materially change the surrounding soil. Here, on
heavy London clay, we have already had to rebuild our garage due to
subsidence, and that's with just the clay's normal reaction to rain and
drought. We are constantly watching for cracks now. Other houses in our
road have also had to be underpinned.

Insurance companies are very aware of the way clay reacts, and charge a
higher premium on building insurance policies where properties are affected.
It would not be wise to undermine your house *and* risk voiding your
insurance policy.

You may, of course, be a surveyor and know exactly what you're doing. I
don't mean to frighten you, but if I have awoken any doubts, please consider
consulting a surveyor (and, perhaps, your building insurer) before it's too
late.

Hope everything goes okay and you get the garden you crave for.

Spider