Tim Downie wrote:
I'm widening my driveway and laying more block paving (standard 20 x10 cm
blocks).

Something that has always annoyed me about the old block paving is the
ability of weeds to set up home in all the gaps.

I know that the recommended way of "setting" the blocks in to use kiln dried
sand but is there any reason not to use a sand/cement mixture and deprive
weeds of a chance to get rooted in the gaps?

This would also mean I could pressure wash the drive without digging out all
the sand.

I used that, but the weeds still come.

But at least you can as you say pressure wash..

Any comments?

Tim