Well, that’s a loaded question. There are different sizes of curbs and gutters… You could measure the top of the curb, the side of the curb, and then the flat part of the gutter to where it meats the pavement. That would be your “width”. Then measure how many linear feet of curb + gutter you have to clean and that would be your “length”. L x W = square footage. Then you could charge your normal square footage price, plus a little extra because the vertical part of the curb will mean a little more work versus simply pushing a surface cleaner on sidewalks.
You’ll also need to account for water access. Sometimes on these jobs water is hard to come by, so you would need to charge accordingly.
