Pressure washers

You just use the water pressure to clean, no need to add any cleaning products. It will remove the moss and algea off paths, slabs etc no problem. Treat the washer with some respect and read the safety bumpf, it really is very high pressure so don't test it with your hand.

 

Just to add to what John says. It will remove dirt, moss and some algae. Sometimes, depending on your paving or the type of algae, it won't remove some algae. You will then need to get an algae remover to put on first. The harder the stone, the less problem there is with removing the algae. Sandstone can be difficult.

Some pressure washers have a bottle that is used for detergent. This is to be used with a car washing attachment and not on paving.

As John says, be very careful what you aim your jet at. Also, try not to hold the jet on any cement pointing you have between the paving. Move over it quickly or you might blast the pointing out.

It is not as bad or difficult as I have made it seem