Turf laying...recommendations pls

[lee]

Hi peeps...just trying to get a little info about laying turf over clay bed.... foundations have been dug for a new large extension...the client wanted to raise an area in the garden with the dug material which is clay.
We did advise her to 'rid' of the clay but anyway.
I have to turf the new raised area...at the moment it holds water in a few places and i am concerned that this may make the turf look patchy.... i will be placing some land drainage to displace the water...just want a general idea of what sort of depth of topsoil i would require so to not blemish the turf with the underlying clay?

lee.

[alan ditchfield]

i think you will find that you will have an ongoing problem with water retention in areas of the lawn even when you have installed land drains, what size of lawn area is this and how deep is the clay.

[lee]

Hi Alan,thanks for the reply...The area to be covered is approx 30m * 8m with a fall across the 8m of around 6 inch's.

The clay is around 1-2 ft deep in places but is level on the surface. I had planned to run some perforated drainage in 3 strips across the 30m width to hopefully keep the balance/ texture of the finish lawn the same.... I will take a photo of the area to be covered...i think this might give you a clearer picture to what i am refering to!

[alan ditchfield]

That is a lot of clay to remove, but it will not be easy to drain as the water will struggle to get to the drains and then escape. I assume you meen three strips running the length of the thirty metres ie;90mtrs of drains not three lengths running across at 8mtrs as these will be too far apart to have much affect on the water retention. it may be wise to incorporate a lot of grit into the sub base as well as the drainage to allow the water to find its way to the drains.