How often should you clean your patio and pavers?

Why bother

Lose the joint sand and the pavers start to shift. A thorough-tier job. Skippable when life's busy, worth it when it isn't.

Why it's a range

Once a year is the standard wash, spring or fall. A damp, shaded patio that greens over fast wants twice a year. A dry, sunny one can stretch to every other year. A sweep and the odd hose-off in between keeps the yearly clean from turning into a battle.

What the job involves

1. Sweep off the loose muck, then dig the grass, weeds and moss out of the joints with a narrow tool, taking as little of the sand underneath as you can.
2. Wash the surface with a paver-safe cleaner or a Dawn-and-water lather and a stiff brush, or a pressure washer kept low, around 1,000 to 1,500 PSI, and never aimed straight down the joint lines.
3. Leave the cleaner to sit 10 to 15 minutes on stubborn stains, then rinse gently so you don't blast the joint sand out.
4. Sweep the displaced sand back in, top up with fresh polymeric sand while you're at it, then mist it with water to set it. Resealing is a separate job, every few years.

Do it yourself, or pay someone?

Yourself, for most patios. A weekend job with a stiff brush, paver cleaner or dish soap, and a garden hose or a pressure washer kept on a low setting. Hand it to a pro if the patio is large, badly overgrown, or due for a full clean-and-reseal. A professional power wash runs $80 to $500, most pay about $250, and a full clean-and-seal is $300 to $550.

What skipping it costs

$300 to $700 is what a forced paver clean-and-re-sand restoration runs on a typical 200-square-foot patio, roughly $1.50 to $3.50 per square foot. That is the bill once the joint sand washes out, the moss and weeds move in, and the pavers lose their grip and start to shift and sink. A routine clean-and-seal by a pro is $300 to $550 by comparison, and a yearly wash with a brush and a hose is the cheap end of all of it. Let it go far enough and you are relaying the lot, against the tens of thousands it costs to replace pavers outright.

Signs it's overdue

• A green or black film, moss or algae spreading across the surface, worst in the shaded or damp corners.
• Weeds or grass sprouting up between the pavers, a sign the joint sand is washing out.
• Pavers that wobble, sit unevenly, or have visibly empty, sunken joints.

When to start thinking about it

A few days' warning does it. Grumpty grumbles 5 days out, then leaves you alone. Mark it done and Grumpty sets the next one, every 12 months, so you can go back to forgetting it exists.

Questions people ask