F wrote:
Anyone know if there are any problems with using sodium chlorate
solution on block paving? The weeds are starting to show but I don't
want to damage the blocks.

TIA

There is no problem using any weedkiller on block paving, except that SC
doesn't work.

Roundup is what you need - around £4.50 for a litre of ready mixed stuff in
a spray gun and an hours work instead of 5 minutes, but it kills the roots,
whereas almost all other weedkillers kill the tops only.

SC is supposed to make the ground unplantable, but the last house I had had
a large paved area at the back and the horsetails and dandelions used to
thrive on the stuff.