Helps protect the surface. Sealer makes spills not fully penetrate into the surface. This does not mean that surfaces cannot get discolored from leaves, oil, food & drink, etc. Sealer makes it easier to clean these stains.
Helps slow down fading from the sun.
Helps somewhat in locking in sand joints.
Helps with color enhancement. Enhancement sealers make the surface color pop again. Clear-coat sealers do not have any impact on color of the surface.
Some sealers have algae and mold inhibitors to help slow down this growth. It cannot totally prevent mold and algae (you cannot beat Mother Nature.)
Sealers, if using a quality water-based sealer, do not make surfaces slippery. If slipperiness is still a concern, a non-slip additive can be added in.
Sealing does not last forever. On average sealers need to be reapplied every three years. The amount of direct sunlight the surface receives is the biggest determinant of the sealer's longevity.
Sealers greatly improve the look of your surface, however that does not mean they will look brand new. Sealing helps old pavers come to life and protect for the future. The biggest part to how a surface will look when completed is how porous the surface itself is.
For Firerock pavers, travertine, and limestone we highly suggest using clear-coat sealers to protect. We do not endorse using color enhancement sealers on these surfaces.
For flagstone surfaces, we suggest either a clear-coat sealer or a color enhancement matte finish sealer be used.
For pavers, any finish, clear-coat, matte enhancement, satin enhancement, or wet-look enhancement sealer are appropriate.
About Polymeric Sand
Polymeric sand is designed to harden in the joints of pavers, travertine and other hardscape surfaces and help interlock them.
There is basic polymeric sand or wide joint polymeric sand. We only use wide joint regardless of the joint width. This has four times the number of polymers vs. basic polymeric sand which helps lock up the sand firmer and stay in place.
It is designed to help mitigate weed growth and ants eating through. While it is very effective, the manufacturers do not guarantee this.
For sand to stay in the joints there must be proper edge restraint on the outside edges.
The base below must be solid and level. If not, the sand will slide through and not properly fill the joint.
Like any sand, areas exposed to heavy water (bottom of gutters for example) are more prone for sand loss.