The Blog


Why do I use blue chalk? Why not white chalk or some other color?  Here’s the number one reason: when I finish a parking lot, the layout marks are still there. The chalk lines, and measurement marks remain until the rain washes them away. I see the beautiful new stripes, and recognize the layout marks for what they are, but civilians like the owner or general contractor won’t necessarily see the layout marks as such, but see them as part of the pavement markings. If I use white chalk, and white paint, to the untrained eye the chalk might look like paint overspray or spills. Blue chalk is obviously not paint and the customer sees it as layout markings that will go away.  I paint blue squares for the handicap symbol on most jobs, but that is different enough that it doesn’t confuse the situation.   Blue chalk is easy to see on asphalt, sealcoat, and concrete pavement, but perhaps most importantly, the customer is almost guaranteed not to confuse it with messy paint markings.


Here’s a quick rundown on the pros and cons of different chalk colors:





Fades Away?


perhaps cheaper, easy to see on dark pavement

Same color as paint, hard to see on light pavement



Easy to see on dark and light pavement. Not same color as stripes

I don’t know, maybe makes you look like Avatar if you get it all over your face?

Color goes away in a few days to few weeks


Easy to see on light pavement, rain won’t wash off

Can be permanent



Easy to see on light pavement, rain won’t wash off

Can be permanent


Day-Glo orange

Shows up well at night under sodium lights





I use a very special blue chalk powder – HQ Marking Chalk Intense Blue by Defi. It’s made differently from the more common blue chalk you can get at the hardware store. It sticks to the line better, the color is brighter and it takes less chalk to make an easily visible line. It’s made of “French Ultramarine” a manufactured version of naturally occurring Lapis Lazuli. It’s also different because it doesn’t clump in humid weather, flows easily into the chalk box, and holds better to the line with less waste and spills.  I can easily snap 10-15 lines before re-chalking. It’s in stock at the PLP Store in 1 kilo (2.2 lb.) squeeze bottles. Right now, Defi HQ Marking Chalk is priced competitively with ordinary chalk from the big box stores.