Cleaning Pavers Without Losing Joint Sand
To clean pavers, treat the moss and weeds first, then wash with a surface cleaner held flat at moderate pressure, never a narrow tip aimed into the joints. Some sand always comes out, so re-sand the joints with polymeric sand once the patio is dry. Most driveways and patios cost $200 to $450 before GST.
Blast pavers carelessly and you strip the sand out of every joint, which is how patios end up wobbly and weedy.
The joint sand is the whole system
Pavers are not glued down, they lock together through the sand packed into the joints between them. That sand is what keeps pavers from shifting, spreading and rocking underfoot. A pressure washer aimed straight into the joints at close range strips it out in seconds, and a patio missing its joint sand loosens and invites weeds and ants into every gap.
So the goal on pavers is a clean, even surface with the joints left as intact as possible, which comes down to angle, distance and technique.
Treat the growth, wash at the right angle
As with any hard surface here, moss and algae in the joints are treated first so they die at the root rather than regrowing in a month. The wash then uses a controlled angle and distance that cleans the paver faces and lifts grime from the joints without excavating the sand out of them.
Weeds and the moss between pavers are the real enemy: pull and treat them at the root, or they are back by the next wet spell. The difference between a patio that stays clean and one that greens up again is whether the growth was killed or merely displaced.
Re-sand and consider sealing
Some joint-sand loss is unavoidable on a thorough clean, so the finishing step is re-sanding the joints once everything has dried. Polymeric sand is the usual choice, it firms up when wetted, locks the pavers, and resists weeds and washout far better than plain sand.
A paver sealer applied after cleaning and re-sanding deepens the colour, stabilizes the joints further, and makes the next clean easier. It is optional, but on a patio you want looking sharp it pays off. Because paver condition varies, the real price comes from a couple of photos and a free quote.