How to Fix Leaking Gutters

Leaky Gutters

Kypros / Getty Images

Project Overview
  • Total Time: 10 - 30 mins
  • Yield: Fix leaking gutters
  • Skill Level: Beginner
  • Estimated Cost: $10 to $20

Gutters keep houses and yards in good shape by collecting roof runoff and sending it away from the foundation. But gutters that leak aren't doing their job properly. It's simple to trace the causes behind leaking gutters, and most fixes take less than half an hour to complete. Find out how to fix leaking gutters by repairing holes, sealing seams, and fixing end caps.

Why Gutters Leak

Most gutters drip a little bit, but it's time to fix the leak when the drip turns into a stream. Here are the top reasons why gutters leak, along with fixes.

Gutters Are Leaking Through Holes

Gutters may have small screw holes created by an installer or larger holes resulting from damage from a tree or ice. Repair gutters with holes by applying metal flashing over the hole with gutter sealant.

Gutter Joints Are Leaking

Gutter seams can leak water, especially if the seams have not been sealed. Downspout elbows or downspout round drops can leak, too. Fix a leaking gutter seam or downspout junction by applying butyl rubber gutter sealant over the seam.

Tip

Seamless gutters run continuously from end to end—no joints. Seamless gutters are always professionally installed.

Gutter End Caps Are Leaking

End caps close the ends of the gutters to prevent water from leaking. Loose end caps will leak water. The end caps may have been installed without sealant. Installing a new end cap with sealant and crimping down the metal will fix the leak.

Before You Begin

Before attempting any fixes, check out the gutters to make sure of the following:

  • Gutters have no standing water: Gutters with built-up, standing water will leak through small holes or seams or they may leak over the top edge of the gutter. Access the gutters on a ladder and remove the clogs.
  • Gutters are properly sloped: Optimal gutter slope, or pitch, for most areas is 1/4 inch per 10 feet. Have the gutters re-installed if the slope is less than this.
  • Gutters are not sagging: Gutters that droop in front will leak. Hold a bubble level on top of the gutter in various places, from front to back. Add, move, or adjust the structural hangers to bring the gutters back to level.
  • Gutters are properly installed: Check that seamed gutters and downspouts run in the correct direction. Gutters should be overlapped so that the top overlap faces the downspout. Downspouts should be fitted so that a male joint is always above a female joint.

What You'll Need

Equipment / Tools

Hole in Gutters

  • 1 ladder
  • 1 putty knife
  • 1 tin snips
  • 1 clean rags
  • 1 hammer
  • 1 wire brush
  • 1 caulking gun

Leaking Gutter Joints

  • 1 metal crimping tool
  • 1 pliers
  • 1 wire brush
  • 1 latex or other waterproof gloves
  • 1 caulking gun

Leaking Gutter End Caps

  • 1 metal crimping tool
  • 1 pliers
  • 1 wire brush
  • 1 hammer
  • 1 screwdriver

Materials

Hole in Gutters

  • 1 gutter sealant (butyl rubber caulk)
  • 1 flashing shingle, 5-inch by 8-inch

Leaking Gutter Joints

  • 1 tube gutter sealant (butyl rubber caulk)

Leaking Gutter End Caps

  • 1 gutter end cap (left or right, as needed)
  • 1 gutter sealant (butyl rubber caulk)

Instructions

How to Fix a Hole in Gutters

  1. Clear Out the Gutter

    Scoop all leaves and debris from the gutter.

  2. Clean the Gutter

    Remove old materials with the wire brush. Clean the inside surface of the gutter with warm water and mild soap. Extend the cleaning another eight to 12 inches beyond the hole to make sure that the entire area is clean. Dry the gutter with a soft, dry cloth.

  3. Cut the Flashing

    Cut the metal flashing so that it is at least one inch wider on all sides than the hole. For a hole 1/2-inch diameter, cut the flashing so that it is a square 1-1/2-inch by 1-1/2-inch.

    Tip

    Gently tap the cut edge of the flashing with a hammer on a flat, solid surface to flatten it.

  4. Spread Sealant on the Gutter

    Spread the gutter sealant over the hole to encompass the area that will be covered by the flashing.

  5. Press the Flashing Into Place

    Press the flashing firmly into the gutter sealant. Smooth over the excess sealant with the putty knife, creating a transition from the gutter to the flashing.

How to Fix Leaking Gutter Joints

  1. Clear the Gutter

    Remove all leaves and debris from the gutter by hand or with a scoop.

  2. Clean the Gutter Joint

    Clean off the joint and several inches beyond with a wire brush. All old sealant must be removed or sanded down flat. Clean off the area with warm water and mild soap to remove all dust.

  3. Apply the Gutter Sealant

    Squeeze a generous amount of gutter sealant over the joint. Use about 1/4 tube for gutter joints and about 1/3 tube for turns. The sealant will shrink as it dries.

  4. Spread the Gutter Sealant

    Spread the gutter sealant into and over the gutter joint by hand. Wear latex gloves. Press the sealant into the seam. Smooth over the top of the sealant to aid with water flow.

    Tip

    Repairing gutter joints in place is an effective fix but repairing disassembled parts is always better. Whenever possible, disassemble the gutters or take apart downspout elbows, clean them, apply sealant to the separate parts, and then assemble them again.

How to Fix Leaking Gutter End Caps

  1. Remove Old Gutter End Cap

    Knock off the old gutter end cap with a sharp rap with a hammer from the inside out (if crimped on). If the end cap is screwed on, unscrew the small metal screws with a hand screwdriver.

  2. Clean the Gutter

    Clean off old gutter sealant with the wire brush. The end of the gutter must be perfectly clean and thin enough for the end cap to be able to fit on.

  3. Dry Fit the End Cap

    Place the gutter end cap onto the end of the gutter. Straighten out bent metal with the pliers, if necessary. Remove the end cap.

    Tip

    End caps are not interchangeable. Make sure that you have purchased the correct end cap, either left or right.

  4. Add Gutter Sealant to End Cap

    Squeeze gutter sealant into the groove on the inside portion of the end cap (the outside will have no groove).

  5. Place End Cap on Gutter

    Press the end cap onto the end of the gutter. Wipe away excess gutter sealant that squeezes out.

  6. Crimp End Cap to Gutter

    Crimp the metal edges where the end cap meets the gutter. Use the crimping tool. While crimping, hold the end cap in place with your free hand.

  7. Add Gutter Sealant

    Squeeze a generous amount of gutter sealant to the inside of the gutter where the end cap meets the gutter. Press the sealant into place with your finger while wearing latex gloves.

Tips for Preventing Leaking Gutters

  • Keep gutters clean: Clean the gutters at least twice a year to prevent leaves and debris from building up and weighing down the gutters.
  • Install downspout screens: Install screens at the tops of the downspouts to prevent leaves from clogging the downspouts.
  • Install gutter guards: Snap screens over the gutters to prevent leaves and debris from collecting in the gutters.
  • Inspect frequently: Every time you clean the gutters, finish by hosing them out. Soon after, check the gutters from below to see if there are any drips.
  • Fix gutter joints: Scrape off and replace gutter sealant that appears to be old or failing. It's easier to do this proactively than when the gutters are already dirty and leaking.

When to Call a Professional

Seamless gutters can be difficult for do-it-yourselfers to remove and reinstall. For damaged seamless gutters, have a professional gutter company create new gutters from metal coil stock on a mobile gutter machine.

FAQ
  • What can I do about leaky gutters?

    One easy fix for leaky gutters is simply to clean the gutters and unclog them. If you have already tried that, check the gutters for holes, plus make sure that the joints between the gutters and the downspout elbows are sealed with butyl rubber gutter sealant.

  • Why is water dripping under my gutters?

    Water dripping under the gutters is normal, but anything more than a few drops may indicate poorly seamed joints or holes in the gutters.

  • What is the best sealant for leaking gutter joints?

    The best sealant for leaking gutter joints is a butyl rubber or urethane sealant.

Article Sources
The Spruce uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. What Is Gutter Pitch or Slope & Why Should I Care? Ned Stevens Gutter Cleaning