Helpful video reference. MrMakeStuff's video "How to STOP Weeds Growing in Block Brick paving Gaps" shows a practical prevention method.
Why washing alone makes it worse
A pressure wash blasts jointing sand out of the gaps between blocks along with the dirt, leaving deeper, emptier joints that are actually easier for weed seeds and silt to settle into. This is why some driveways look worse for weeds a few months after a wash than before it.
Re-sanding is the first real fix
Filling the joints properly with kiln-dried sand after washing closes off the gaps weed seeds need to establish in the first place. We include this as standard on every block paving job, not as an optional extra.
Polymeric sand lasts longer than standard sand
Standard kiln-dried sand typically needs topping up every 6-12 months. Polymeric sand, which sets harder in the joints, can last significantly longer, sometimes several years, before it needs redoing, which means fewer weeds getting the chance to establish in between.
Sealing locks it all in
Once the paving is clean and properly re-sanded, a sealant helps hold the joint filling in place and adds another barrier against weed growth. See our pricing page for the sealing add-on.
Regular brushing helps between full cleans
A monthly sweep to clear leaves and general debris off the paving before it settles into the joints is a small habit that meaningfully slows how fast weeds get a foothold again.
Sources: GoodGrow UK, "How to Kill Weeds on Block Paving"; Pave Direct, "How To Stop Weeds in Block Paving".