A home's gutter system controls the flow of rainwater. This protects your home’s roof, walls, foundation and landscape. If debris builds up in them, it could lead to sagging gutters, mold growth, wet basements, a leaky roof or water damage to the interior or exterior of your home. Gutters filled with debris also make nice homes for rodents and other pests. Letting your gutter maintenance go can lead to costly repairs down the line.