Originally Posted by Blossom

Have you tried ROUNDUP? It's pretty lethal. Kills all the weeds in our concrete pathways. But of course new weeds/moss will always germinate again, so you need repeat treatment every few weeks.

Spray-on bleach is also effective.

Also, before applying the chemicals, sweep the surface moss away with a stiff broom.

This problem is one reason we'd never have block paving. Good quality concrete slabs and/or selected gravel can give a really professional look, without weed or moss problems. We have a crazy paving patio in cotswold slabs and gravel/slabs in the front. No moss.