How to Repair Gutter Leaks

A man inspecting a gutter
What You'll Need
Extension ladder
Steel wool
Warm water
Sealing putty
Plastering trowel or utility knife

Gutter leaks can cause large amounts of water to flow down the side of your house which can cause cosmetic or structural damage. Gutters are used to collect excess water during rainfall which will be diverted away and drained. Gutter leaks often appear at joints and downspouts and need to be fixed quickly to prevent damage to the structure of your roof or home. This can be done easily by a novice DIY enthusiast.

Step 1 - Scrub the Crack

Use an extension ladder to gain access to the gutter. Once the leak point has been pinpointed, scrub the area around the crack to remove any buildup. The area needs to be clean so a small replacement sheet of plastic will fit tightly into place. Use a small piece of steel wool and scrub the crack gently to provide a clean, etched surface. Have a small pot of warm water on hand to dip the wool into frequently. The damp wool helps to reduce dirt and debris. Once the area is thoroughly cleaned, use a piece of sandpaper to smooth the edges of the crack. If any plastic fibers from the steel wool are stuck in the crack, remove them using a pair of scissors.

Step 2 - Replacement Patch

Cut a small replacement patch of strong plastic material. A large pair of scissors will be needed to cut through the thick plastic. If possible, use the same type of plastic that was been used for the gutter system. This type of plastic can be purchased from building supply stores. Make sure the plastic material is both strong and durable plastic to ensure it will last in varying weather conditions. Some plastics will last for a long time even though they will be subjected to constantly varying temperatures and moisture. Carefully cut an even square or rectangular shape from the piece of plastic. It's important to cut the plastic to a size that covers the crack and leaves a border roughly one inch wide around the perimeter of the crack. This will ensure the crack is completely covered.

Step 3 - Apply Patch

Container of sealing putty

Apply a small amount of sealing putty to the back of to the plastic patch. Use your fingers to spread and mold the putty evenly onto the entire back of the patch then press it into place. Make sure the crack is completely covered from top to bottom and hold the plastic in place for a few seconds allowing the putty to set. Do not worry about any excess putty that oozes out as it will harden and can be easily removed later. If you have not cut the patch large enough, remove it before the putty has a chance to solidify. Make any adjustments to the size of the plastic needed, remove the putty from the crack, and reapply the newly cut plastic patch.

Step 4 - Tidy the Patch

Once the patch is set and the putty has hardened, use a plastering trowel or utility knife to cut away any excess sealing putty around the crack. This will help to make the replacement patch look more professional. The final result of the repair process is a small plastic patch attached to the crack in the gutter using strong putty, which stops the water leaking problem.

Step 5 - Check Your Gutter

The final step is to run a test to check that the gutter leak has been completely repaired once the sealing putty has had time to dry and harden. To do this, pour a small amount of water down the gutter and check the area that was repaired for any signs of water leaking from the crack. Water should not be able to penetrate through the putty after it has solidified. If there are signs of water leakage, apply a small amount of the putty to the under side of the gutter. Smooth the putty over the gutter and allow to dry, then repeat the water test.

Once the test has provided negative results showing no signs of leaking, you can rest easy that the gutter is repaired and the patch is doing its job. To ensure there are no future issues, frequently check the gutters for leaks and make repairs as needed.