By limestone screening, do you mean crushed stone and sand? Where are you located and what is your soil like? Around here (New England), the crushed stone and sand add stability to keep the slabs from heaving, and to allow water to drain. They aren't for weed control. If you're building this on sandy soil, you may be okay doing without the stabilizing layers, but I wouldn't be willing to risk it .. unless the soil is ONLY sand.

This post was edited by Chibimimi on Sun, Jul 14, 13 at 22:23

Don't use the fabric! It's nothing but a big waste of money since the weeds still come thru. Someone on another forum recommended cardboard or newspapers. My sister used old carpeting and said it's the best thing yet, absolutely no weeds! Years ago my husband used black pastic, and we never had weeds either. It's not recommended to use, but I don't know why.

Weed seeds usually come from the top, not underneath. Unless you have a area that is weedy or grassy already and you are not going to clear it off, I would suggest that you use newspaper or cardboard as they will smother out the weeds and grasses that might come up from under the pavers. Carpeting or carpet padding would probably work.

Black plastic won't let the weeds come up but it will not drain and you might get standing water.

Weed seeds are going to land in the cracks and come up, whatever you use. Can't really prevent that.

Sandy