Relaying garden paving to stop weeds coming through again

It is very unlikely that the weeds have NOT come through from the sub base, they more than likely have grown down the joint in the slabs into the sub-base when a seed as drop in. The times I have had arguments that weeds are growing through my slabs or block paving you wouldn't believe but its not the case, if you have weeds in your drive or patio just spay with Round up or a another type of bio-degradable spray to get rid of them, re seal the joints after power washing with silver sand Peter

Alternatively before you lay any slabs / decking i always lay down a heavy duty weed suppressant membrane to help deter this problem. It may seem a pointless exercise but in the longer term if does help.