Block paving as a natural mineral substrate, contrary to popular belief amongst homeowners, will absorb moisture. This is because cement, stone & brick are all porous, meaning water can transfer easily through the pores of the material. The more porous the paving, the more water it can absorb.
On Using Pavers for Landscapes
Pavers are great for patios, since they allow water to seep through and not form puddles and pools.
The result is a deposit or 'salt' that appears on the surface of the paving. There's no single, definitive appearance - it is sometimes powdery, sometimes scummy: sometimes it's hazy and indistinct; sometimes it's sharp, crisp and obvious.
Just as it appears naturally, efflorescence will eventual- ly disappear. Over time, rainwater can wash and wear it away.
Efflorescence alone does not pose a major problem, but it can be an indication of moisture intrusion, which may compromise the structural material. Building materials, such as concrete, wood, brick and stone, are porous materials. Porous materials can absorb or wick water by a process called capillary action.
An influx of water that sits for a long period of time can damage your paver surfaces by weakening the cracks or chips already present. If your pavers are already loose, they may collapse. Flooding can also lead to erosion when soil and rock are transported and deposited into the area.
The first is to make sure the pavers are dry. Not just the surface but most of the way through. That means that if it has rained for three days, then stops, and the sun pops out you can't just run out and put down sand. The water will wick up through the pavers and cause stains.
Some paver sealers can provide a glossy sheen or "wet" look which many homeowners like. Not only do these brick paver sealing products enhance the natural beauty of the pavers with a shiny gloss look, but they also waterproof and protect against the elements. Paver sealer can also keep your pavers cleaner.
Tips for Pavers Sealing
Use a pressure washer to remove any dirt, dust, or debris accumulated on the surface of your pavers. Make sure your pavers are dry before applying sealer. If your pavers are wet, the sealer will not be able to adhere properly and will eventually peel off. Apply the sealer in thin, even coats.
When warm air comes into contact with a colder temperature concrete slab, the condensation will build up on the surface and can commonly be defined as concrete sweating. The combination of temperature swings and humidity build up cause the concrete to sweat.
Therefore, keeping track of the weather can help you avoid sealing before impending rain. If a storm does occur before sealant application begins, consider waiting at least 24 hours until the dampness evaporates. If the pavers are wet due to a pressure wash, allow them at least 24 hours to air dry.
Sealing your pavers will inhibit algae and mold growth. Sealed pavers dry quickly which will minimize mold growth caused by moisture and humidity.
If your pavers have been sealed, which is a service that we offer, it's a lot easier to maintain and it does slow down mold growth for the simple fact that when your pavers are unsealed, that moisture will sit in the joints and make mold grow. Mold likes damp, dark areas.
Streaks & Lines – Pressuring washing improperly can leave unsightly streaks, swirls & lines all over your hardscape. Permanent Damage – Not using the right tips, holding the wand too close to the pavers and poor technique can result in permanent damage to the surface of the pavers.
Standing water weakens pavers, leading to chips, cracks, and even erosion. During colder weather, water that gets into these cracks and crevices can freeze, causing cracks to expand and worsen. To prevent pavers holding water, you want to invest in draining the pavers.
Theuse of polymeric sand increases the durability of the entire surface of the landscaped area. This minimizes the opportunity for water to seep below the surface of the interlocking pavers and into the sand and/or crushed stone foundation below.
As stated previously, most efflorescing salts are water soluble and many will disappear with normal weathering unless there is some external source of salts. In general, most efflorescence can be removed by dry-brushing followed by flushing with clean water.
A few major differences between efflorescence and mold growth: Mold grows, efflorescence doesn't. Mold can grow on just about any surface, whereas efflorescence doesn't spread. Mold is a fungus, whereas efflorescence is moisture that evaporates into salt deposits.
The acidity in the vinegar helps remove the efflorescence and calcium deposits by breaking down mineral crystals. After cleaning the surface, let dry for 48-72 hours (moisture content below 25%).