Pressure Washing Sandstone Pavers and Walkways
Pressure washing sandstone pavers is a simple and rapid way of cleaning them, with brilliant results. When the pavers have been sealed and have resilient grouting, and when you keep the pressure washer on a spray width and pressure not a lot more than that of a high pressure hose, this becomes an easy task with results that will brighten your day!
As sandstone is quite porous it easily absorbs not only water but also any staining substances the water may contain. When it is sealed however, it is easy to keep clean and to maintain its naturally beautiful colours and texture.
Sandstone pavers are usually cleaned and sealed before they are set into the walkway. The sealant needs to be deeply penetrating, again because of the porous nature of the stone. (It can be sprayed onto the pavers from a spray bottle.)
Once set into the ground, a second coat of the sealer can be applied. For this, wait until the sand and grout are completely dry, then ensure that the sandstone is quite clean at the time of sealing. For this in-ground sealing, a bucket and mop can be used instead of the spray bottle. Once the sealer is spread over all the pavers, leave them overnight. You can then repeat the mopping process the next morning if that is warranted.
The pressure washing process for cleaning sandstone pavers is very straightforward, as seen in the video above. As for detergent, harsh chemicals are not needed. Depending on the state of the pavers, water alone may be sufficient. Some people even use dishwashing liquid.
A word of caution: The pressure washing process used on sandstone is effectively a soft wash. Use low pressure and a wider fan spray, and keep the nozzle about 30 - 40 cm from the surface. Sandstone is a soft rock and a powerful, high pressure jet spray may etch into the surface.