This how to guide will be useful for individuals and contractors alike. We are commonly asked, “What is the best way to remove our parking lines?” this question is usually followed up with “Will that hurt the concrete underneath?”. The answer to these and other questions will be answered below.
There are many ways to remove pavement markings, from grinding to chemicals and everything in between. Here is a list of the most common, and what type of impact you should expect to see on your pavement.
is a process in which a grinding wheel (typically Diamond) is used to remove the markings. Disc grinding can be an effective way of removing markings from a polished concrete floor, such as those found in a warehouse. The process can be very time consuming but will ultimately provide a very smooth finish on the concrete. After all, Diamond grinders are what is used to polish a concrete floor. These machine are available in many orientations, from a small hand grinder Blastrac BL-233, to a large gas powered walk behind unit EDCO TG-10. While both of these machines will work, you must decide what type of production will be required. Blastrac and EDCO both have excellent machines and customer service, for more information contact them direct.
uses a rotating wheel of cutters that can be made of Steel, Carbide, or other various metals. Rather than rotating horizontally like a disc grinder, a scarifier drum rotates on a vertical axis with many small cutters attached to it, thus prolonging the life of the cutters and allowing for the reuse of the drum. Scarifying leaves a textured finish, this could be compared to the finish that a leaf rake would make in sand. This can be considered a less than perfect finish and is not recommended for areas that need to be very aesthetically pleasing. Scarifying is commonly used on roadways to remove lines, however in recent years many Local and State DOT’s have moved away from scarifying due to the “ghost lines” it creates (a line that is visible but not meant to be).
Water Blasting (40,000psi+)
is a process that is commonly used for removal of pavement striping on roadways and airports. Water Blasting is sometimes confused with Pressure Washing, but they are 2 very different machines. A Water Blasting machine is typically mounted on a truck that is dedicated to the process, they use extremely high pressure pumps that are very large. Units like the Stripe Hog 5000 can sell well over $250,000 and are typically reserved for those requiring a very high production rate. The finish of the removal is quite good, there is minimal “ghosting” and little to no damage to the pavement.
Pressure washing as stated above is commonly confused with Water Blasting, while it can be an effective method to clean pavement, it is not a good choice for removal of parking lot striping. I have seen contractors and maintenance men spend hours trying to remove 1 handicap space. In my opinion, Pressure washing should be reserved for cleaning purposes only.
Soda Blasting is the process in which you use baking soda (yes the same stuff that is in your toothpaste) as a blasting media in a machine that is similar to a sandblaster. The same basic principles apply, they use pressurized air and a media, in this case Baking Soda, to remove whatever they come in contact with. Why use Baking Soda? well, the soda used literally explodes away surface materials without damage to the substrate. Soda is also a non hazardous food grade material that is 100% water soluble and environmentally safe. The pavement typically sees very little to no damage from Soda Blasting.
is just as it sounds,and most of you will know the process. Just as with Soda Blasting, Sand Blasting uses pressurized air and sand, which is then shot through a nozzle to control the intensity and direction. Sand Blasting is a fairly cheap and easy way to remove parking lot striping, however it does require hiring a contractor typically. One downside to Sand Blasting is the dust and debris it creates, this is typically required by most municipalities to be cleaned up and properly disposed of. Sand Blasting can leave an unpleasant look to the pavement but will go away in time.
Shot Blasting is very different than the Sand and Soda Blasting mentioned before. The process for Shot Blasting is a very clean yet expensive one. Steel shot is propelled by a rotating drum or wheel through a manganese steel housing, which cleans the surface much like other blasting methods. Shot Blasting is commonly used when no contamination can be present as the media is little steel BB’s that are very clean. Shot Blasting can create a very rough surface that will last for a very long time. This is a process that we recommend you hire a professional for, however when properly done, Shot Blasting can be a very good way to remove markings.
There are many chemical paint strippers on the market. I do not typically recommend them due to the discoloration and damage they can cause to asphalt and concrete. If you do need to use a chemical remover, be sure to consult the manufacturer and follow all the required safety precautions.
unfortunately, many customers and contractors use or want to just Black Out the striping. This is where you paint over top of the lines with a black paint, while not the best way to go about it, it can be effective. should you want to black out lines I suggest using one of our Line Stencils in order to keep the paint on the lines from before. Black Out will not damage your asphalt or concrete, but you will have to constantly re paint it as the black wears off.