We always recommend shot blasting to prepare surfaces ready for line marking. If you’ve had line laid before it’s essential to remove all traces of the old markings, if you’re having lines marked on a surface that doesn’t have existing markings shot blasting is still important as it removes the top layer of concrete and any dirt or marks and creates a surface with the optimum bond for the markings. Shot blasting will increase our time on site while we do this key surface preparation but how long it takes depends entirely on the type of line markings to be laid. A simple two-lined walkway with a walking man symbol requires two shot blasted lines and a small area for the symbol. A heavily marked area with zebra crossings or full demarcation requires a much larger surface area to be shot blasted before marking.