While seamless gutter systems are easy to maintain, it is important to clean them at least once per year. For systems without a guard, it is essential to remove any dirt and debris from the system to keep water flowing to prevent it from spilling back onto the roof or siding. Part of any annual maintenance should include checking that the gutters are still sloped correctly, and everything is properly attached. A residential contractor that specializes in gutters will have the equipment and knowledge to best maintain rain gutters.