I quickly learned that red and even blue chalk lines leave almost indelible marks on composite decking. My solution is to keep a chalk box filled with white chalk, for results that can easily be washed away. Stanley’s white marking chalk works the best and should be available at your local lumberyard or building supplier. If you can’t find any, there’s always baby powder. To fill my chalk box from the container, I just fold a sheet of paper down the middle, dump some powder on the paper, and then use the paper as a funnel to slide the powder into the opening.

Dennis Rohan is a remodeler and deck builder in San Juan Capistrano, Calif.