How to Make a Waterproof Seal in Gutter Joints

Climb up a ladder to inspect the leaky joints for damage. A broken silicone seal or debris can cause a leak.

Remove all water and debris built up in the gutter. Use a scouring pad and toss the water out of the gutter with your hand. Add dish soap to the scouring pad and scrub the bottom of the gutter while expelling the water. Remove all debris such as twigs and leaves.

Scrub the rest of the gutter work area with a scouring pad and dish soap. Wash the gutter out with clean water and dry it with paper towels. Make sure the entire work area is completely clean before continuing. Any left over dirt, debris or water can prevent the silicone adhesive from adhering to the gutter's surface.

Look at the ends of the gutter to see if you can find a manufacturer's name. If so, you can find a silicone sealant made specifically for your gutter's brand name at your local hardware store. If not, standard silicone sealant works fine.

Apply a generous amount of silicone sealant to the broken joints. Cover both the inside and the outside of the joints. Make sure to cover the joints completely with sealant as it shrinks during the drying process. Allow the sealant to dry. Your gutters should now have completely waterproof joints.