How to Prevent Moss on Paver Patios in BC

Why Moss Loves Fraser Valley Patios

Moss is not a sign that your patio is failing. It is a sign that you live in British Columbia. Our combination of heavy rainfall, mild winters, and shaded backyards creates perfect conditions for moss and algae to colonize any outdoor surface. In Abbotsford, most patios spend at least five months of the year in conditions that moss thrives in: persistent moisture, temperatures above freezing, and reduced sunlight. North facing patios and those shaded by mature cedar or Douglas fir trees are especially vulnerable.

The good news is that moss is a surface issue. It does not damage the pavers themselves. Left unchecked, it does make the surface slippery and gives the patio a neglected appearance, but with the right approach you can keep it under control without spending your entire weekend scrubbing.

Polymeric Sand as Your First Defence

The single most effective thing you can do to reduce moss on a paver patio is to install polymeric sand in the joints. Standard joint sand stays loose and provides gaps where moisture, organic debris, and moss spores settle and take root. Polymeric sand hardens into a semi flexible joint that blocks moisture penetration and prevents organic material from lodging between pavers. On every patio we build in Abbotsford, polymeric sand is standard, not optional. If your existing patio has regular sand in the joints, switching to polymeric is the highest return maintenance step you can take.

Cleaning Methods That Actually Work

For light moss, a stiff push broom and a garden hose handle the job in spring. For heavier growth, a pressure washer on a moderate setting (around 1,500 to 2,000 PSI with a wide fan tip) clears moss quickly without damaging paver surfaces. Avoid turbo nozzles and anything above 2,500 PSI, which can pit softer pavers and blast out polymeric sand. After pressure washing, let the surface dry for 24 hours, then reapply polymeric sand to any joints that were disturbed. We recommend this deep clean once a year in late March or early April, just as Abbotsford comes out of the wet season.

Preventive Treatments and Ongoing Maintenance

After cleaning, applying a moss preventive product like Wet and Forget or a zinc strip treatment along the roofline above your patio creates a slow release barrier that inhibits regrowth. Zinc strips work the same way they do on a roof: rainwater washes small amounts of zinc across the surface, which moss cannot tolerate. Keeping nearby trees trimmed to allow more sunlight also makes a real difference. Even an extra hour of direct sun per day during summer can significantly slow moss establishment during the wet months that follow.

Sweeping leaf debris off your patio in fall is another simple step that pays off. Decomposing leaves create a damp organic layer that moss loves. Keeping the surface clear and dry whenever possible removes one of the key ingredients moss needs to establish.