heavy soil how to improve it cheaply?

[clarelouise]

Hi
We have heavy soil in our garden.
We found a very small amount of clay in one area but not in a lot of other areas.
It is mostly a cloggy, heavy soil.
We are preparing our site for seeding a lawn.
Around 55 sq metres.
Advice please on how to improve the soil for sowing the grass seed cheaply.
We don't want to buy topsoil if possible as we have excess soil as it is.
Also weeds have come up over past few weeks over site we dug last summer.
Back to square one.
Treated them with weed killer last year but back again.
What is best weed killer to use to kill well and to be able to sow seeds in next month for lawn.
Thank you in advance for your replies.
Much appreciated.
Clare.

[landscaper2]

These are probably weed seedlings that have lain dormant in the ground. Ue a weedkiller containing Glyphosate, such as 'Roundup' now. With the 'heavy' area, if you are planning to sow seed soon, then I would think the only way of improving the ground would be to roughly level the ground and spread about an inch sharp sand over the surface and rotavate into top 3 or 4 inches.