Paver Sealing in Tacoma, Before Rain and Moss Do the Damage.

Not always. The paver industry's own technical guidance treats sealing as optional for many installations. Sealing does not make pavers stronger or change how much load they carry. What it does is reduce how much water, oil, and dirt soak into the surface, help hold joint sand in place, and deepen the color.

Around Tacoma, sealing earns its cost in a few situations. Driveways where cars drip oil. Patios under trees, where leaves and needles stain the surface. Shaded areas where moss and algae take hold. Joints that keep losing sand under downspouts or on slopes. Patios next to a grill or outdoor kitchen, where grease lands.

If your pavers are in full sun, drain well, and you like the natural weathered look, you can skip it and just keep the joints full and the surface clean. We will tell you that during the assessment.

Moss grows on pavers here because the surface stays wet and shaded long enough for spores to settle in the dirt that collects in the texture and joints. Sealing helps by making the surface shed water and dirt, and by keeping organic debris out of the joints. It does not kill moss, and it does not change the shade.

The order matters. Moss and algae must be removed and the surface cleaned before any sealer goes on. Sealing over growth locks it in and makes the next cleaning harder. If moss always returns in the same spot, look for the cause: a downspout, a planting bed draining across the patio, or a low spot that holds water. Fixing that does more than any product.

Between sealings, blow off leaves and needles regularly in fall. A pile of wet maple leaves left on pavers for a month leaves a stain sealing cannot fully prevent.

Efflorescence is a white, powdery haze that shows up on concrete pavers. It comes from the cement: calcium hydroxide dissolves in water, moves to the surface, and reacts with carbon dioxide in the air to form calcium carbonate. Industry guidance says it does not affect the strength or durability of the pavers. It is a cosmetic issue.

Timing is the key fact for sealing. Industry guidance says efflorescence can peak as soon as 60 days after installation and can stay for months. If the pavers were installed in a dry stretch, it may not appear until the next wet season. In our climate, that means a summer install often shows efflorescence in fall.

Do not seal over it. Sealing over efflorescence traps the haze under the sealer. Remove it first with a cleaner made for concrete pavers, tested on a small hidden area. Industry guidance recommends sealing after efflorescence is under control, and using a breathable sealer if you expect it to come back.

There is no single best sealer. The right one depends on the look you want, what the surface sees, and whether moisture will keep moving through the pavers. This is how the main families compare, based on industry technical guidance.

In a rainy climate, the joints matter as much as the surface. Joint sand locks pavers together. When it washes out, pavers loosen, water reaches the bedding faster, and settling starts. Sealers soak into the top of the joint sand and help hold it. Dedicated joint sand stabilizers do that job more strongly.

Industry guidance recommends stabilizing joint sand on slopes over 7 percent, and notes that pavements that get regular heavy rain, concentrated water under eaves, or water from downspouts benefit from it. That describes a lot of Tacoma patios.

For liquid stabilizers, the guidance says the product should penetrate at least three quarters of an inch into the joint sand, and that the joints must be full and compacted first. That is why we inspect and refill joints before any sealer goes on. Sealing half-empty joints glues the top of the problem in place and leaves the rest.

Cleaning is most of the labor in a sealing job, and it decides how the finished surface looks. The sequence below follows industry guidance for concrete pavers.

The wet season is the main scheduling constraint. A sealer applied to damp pavers, or to joint sand that is still wet underneath, can turn cloudy or white. Industry guidance lists wet surfaces and joints, a poorly draining base, and a sealer applied too thick as the common reasons.

That means we need a dry window on both sides of the job: dry before application, and dry while it cures. Guidance says to keep traffic off until the sealer is completely dry, typically 24 hours. Late spring through early fall gives the most reliable windows. We will not seal on a day that only looks dry if the forecast or the joints say otherwise.

Keep cleaner rinse water and moss treatments out of the storm drain. Tacoma's washing discharge guidance, written for businesses, allows only cold water with no soaps, detergents, or other pollutants to reach storm drains from washing sidewalks and exterior surfaces. The same rule of thumb is the right one at home.

Industry guidance does not give a fixed reseal interval. It says the timing depends on use, climate, and the quality of the sealer. Instead of the calendar, watch the surface.