board rack for vertical bars (no cross bars) volvo XC90

whats a good rack to use if we have vertical bars (no cross bars) our car is a volvo XC90. will the removable rack possibly mess up the foam or make a lot of noise since we sometimes have to drive hours to get to the spots. I live on the great lakes so the only times theres waves are when the winds howling and its not quite the nicest day outside.
later
-henry
later
-henry