In article , Johnboy
writes
My lawns are looking very poor, 60% moss, plus white patches.

I think the problem is due to the turf being layed over heavy clay soil,
actually I know this is the problem, new build syndrome, will top dressing
do any good and if so what mix should I use?

The ideal solution would be to remove a foot of clay all round and introduce
some organic material and fresh soil but I cant afford this.

Some moss in spring and autumn is a fairly common feature in many lawns.
60% is rather high but it is almost certain to drop rapidly as the lawn
matures. Neither top dressing nor new soil should be necessary. If you
mow the lawn to a regular height and don't allow the turves to dry out,
grass roots will develop into the clay and the moss will soon recede.
--
Alan & Joan Gould - North Lincs.