When to Sandblast the Old Paint in Your Parking Lot?
Every parking lot requires striping and pavement markings. This includes everything from parking stalls, to handicap lanes to fire lanes and stencils. Over time this paint begins to fade and chip. Most often, a fresh coat of paint is simply applied over the top of the old layer of paint but if the underlying paint is failing, the new layer of paint will chip with it, causing your newly-painted parking lot to look old within a matter of months. The old paint must be removed in order for the fresh paint to stick.
Sandblasting is the most well-known method for removing old paint in a parking lot. But is it always the best option? Sand blasting is the process of using compressed air to shoot sand or a silica-free abrasive material on paint to remove it. It is highly effective but requires a lot of materials, set up, clean up and time, making it relatively expensive. Because of the cost, property managers and owners should only use sandblasting when necessary.
Alternatives to Sandblasting
There are other alternatives for removing old paint depending on the situation. They are power washing and grinding. Power washing is the process of using a high pressure stream of water to remove loose paint. Grinding requires a specialized machine that spins a rotary diamond blade to remove paint.
Power Washing to Remove Old Paint
Power washing is the method we use most often to prepare old parking lot paint for a re-stripe. We use high pressure 3,500 psi water and a special rotary nozzle that will agitate any loose and chipping paint and remove it. This method does not remove all the paint or even most of it. It simply removes the paint that is chipping or is going to chip in the near future. This is also the most cost-efficient option. We only use this option in re-striping situations when the underlying paint is in relatively good shape.
Grinding to Remove Old Paint
Grinding removes paint completely. It is slower than sandblasting but requires much less set up time. This makes it a good option when small areas of paint need to be completely removed (such as arrows or reserved parking stencils) or when paint needs to be removed around sensitive areas that could be damaged by sandblasting (such as storefronts).
When Sandblasting is the Best Option
Sandblasting is the best option when large areas of paint need to be completely removed or when there is pervasive chipping of the underlying paint.
The photo above is a good representation of pervasive chipping. The paint on this curb had to be completely removed by sandblasting. We then re-striped the fire lane.
If you have old paint in your parking lot and need an opinion as to whether or not it needs to be sandblasted, please contact us for a free assessment.