Posted: 14/04/2014 at 17:50
You could do with digging a test hole to see how compacted the soil is before adding top soil.
If it's badly compacted dumping topsoil on top will leave you with a solid pan underneath which will just hold water and you will be throwing money down the drain.
I don't know whats caused the compacting but in my opinion you'll need to go down at least a foot to break the top layer up. If you do rotavate to that depth you won't need topsoil.
Breaking the top layer up and leaving the sun and wind to dry it for a week will leave you with an almost perfect base to sow seed and after the seed has taken you can top dress to level any bumps or holes.
It just seems an expensive way to do it.