How to Repair Leaky Gutters

Text: Leaky Gutters | Background Image: Gutter Water Overflow from Gutter

Leaky gutters are an invitation for myriad costly home repairs. From water damage in the basement and foundation to streaked or damaged siding, you’re in for it! Fortunately, repairing leaky gutters isn’t hard and will save your home from serious damage in the future.

In this article:

Why Gutters Leak?

Reasons for gutter leaks could range from faulty installation and corrosion to cracks, holes, or tears in the gutter system. Let’s take a look at a few common ones in depth:


Gutters take a lot of punishment from natural elements that can wear them out over time. Older gutter systems are more prone to this as the design, material, and manufacturing methods of 20-30 years ago don’t really live up to today’s standards. For example, the rubber seals on older gutters have a shorter lifespan than newer ones, and sealing agents are stronger and more durable today. So, if you have older systems running around your home, they are likely to spring a leak if not cared for. 

Improperly Installed of Maintained

Rain gutters are located two or three inches from the edge of the roof. If they’re too far, the gap will let water seep through. Your gutters will eventually start sagging and tilting away from the roof. 

A misplaced gutter could be due to either a calculation error at the time of installation or lack of maintenance, causing them to be unstable. Gutters attached with fasteners to the fascia board also become loose with time. 

Wear and Tear

Gutters hang at the edge of your roof and are often susceptible to damage from ladders, heavy debris, leaf buildup or heavy snow. These things will stress and damage gutters.

Heavy impacts during stormy conditions may also crack a gutter and compromise the integrity of the whole system. In addition to cracks, gutters pulled away from the fascia due to the reduced compressive strength of the seals create another escape route for water via gaps.

Expansion and Contraction

Most gutters expand in heat and contract in cold. You might’ve heard your gutters creaking or clicking on a warm day, these sounds occur when they expand and rub against the brackets. 

Modern gutter systems are designed to withstand expansion and contraction, which is why they come with insertion marks on the inside to tell you how far you need to push the gutter in. This allows the material to expand and contract with changing temperatures without compromising the seals or structural integrity. 

The repeated contractions and expansions can pull apart seams or pop gutters out of support clips. 

Sagging Gutters

Sagging Gutters
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The bolts on your gutters can come loose from buffeting wind, or when the wood in which they are anchored rots. When that happens, they may tilt or sag to one side and rainwater can spill over the top. In heavy downpours, sagging gutters may even collapse and damage whatever is underneath.

Clogged Gutters

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Stones, leaves and other debris collect in the gutters, especially in autumn, and obstruct rainwater from flowing freely. And when it has nowhere to go, the water starts to drip along the sides. 

Dirt in the Seal

This is common for homes in colder climates. Cold temperatures make the gutters contract. As they “shrink,” they can draw bits of grit and sediment into the joint, keeping two sections of gutter from maintaining a tight seal.

Improper Pitch

Gutters need to be installed on a slight incline so water flows directly toward the downspouts and harmlessly to the ground below. Water will accumulate in gutters that are not properly pitched and eventually overflow the front of the gutter.

Signs of a Leaking Gutter

Water dripping from the roof and gutter is a tell-tale sign that something is wrong, but in some cases, a leak can go unnoticed. If the damage is minimal and subtle, chances are you won’t be able to spot a gutter leak until it escalates and causes real damage.

Keep an eye out for a few common signs of a leaking gutter. They usually include:

  • Paint peeling near the base or underneath the gutters 
  • Visible cracks on the gutter
  • Water stains or marks under the gutters
  • Clogged gutters or downspouts
  • Signs of rust
  • Damp, cold, or damaged interior walls
  • A musty smell inside the home
  • Water pools or water streaks down the edges of your basement
  • Appearance of termites as they flourish in damp environments 

Problems Caused by Leaky Gutters

Leaky gutters can make your home’s structure and foundation vulnerable to serious damage and also cause unsightly streaks on your windows and siding.

Simply put, your gutters quit working when they leak. If left untreated, leaks can result in issues like: 

  • Roof and fascia damage due to constant exposure to moisture, which may also lead to rotting wood and roof problems
  • Damaged or cracked foundation due to water pooling near the foundation
  • Soil erosion and damage to your garden and landscaping
  • Cracks and water damage in driveways
  • Basement flooding 
  • Worn out the gutter, sometimes to a point where the gutter would fall off and damage the soffit, roof, fascia, and the ground below
  • Rotten porches and decks if the water is falling on these structures
  • Mold growth on outer walls
  • Clogged gutters

How to Repair Leaky Gutters

After you spot a leak in your gutter, fixing it will generally include three steps: clean, repair, or replace. You will need the following tools to fix a leaking gutter: 

  • Gutter sealant (rubber sealant or silicone caulk)
  • Gloves
  • Plastic scouring pad
  • Garden trowel or putty knife
  • Rubbing alcohol or denatured alcohol
  • Drill 

Here are some common problems and simple fixes:

Repairing Joints and Seams

Step 1: The first step to fixing any gutter problem is to clean it out. Scrape or scoop out any debris from the gutters, especially along the seams and end caps. Use a putty knife to catch all the leaves and other buildup. 

Step 2: Use a plastic scouring pad to scrub the area around the joint and wipe it down with rubbing alcohol or denatured alcohol to get rid of rust. You can also use a wire brush to do so. If feasible, flush out the gutters with a garden hose and let them dry. 

Step 3: Unclip the gutter length above the affected seal. Clean up any remaining gunk from surrounding parts. 

Step 4: Get a good-quality waterproof and weatherproof gutter sealant and apply it to the inside edge of the seam or at the end cap joint. Silicone and butyl rubber sealants work best for sealing leaking gutter joints. 

Make sure you apply sealant with a sealant gun and exert steady pressure so the sealant can go deep into the joint. Spread a small amount of sealant on the area surrounding the joint and smooth it out so it doesn’t create a raised ridge that will impede water flow. Wait for it to dry anc cure fully(about 24 hours), then flush some water through the gutter to test the seal.

Sealants are easy to apply and quite flexible to allow movement so your gutter can withstand temperature changes without cracking.

Step 5: Reattach the gutter to the insertion mark in the fitting to create a new seal as it squeezes into the sealant. 

Repairing Gaps, Holes, and Cracks

Step 1: Clean up and prepare the gutter before you fix it. The area should be clean of leaves and debris buildup. Exercise caution when using a ladder, and use protective gloves to make sure you don’t injure yourself in the process. 

Step 2: Apply a commercial-grade sealant formulated to seal exterior gaps. The sealant needs to be flexible after application, and resistant to weather changes and UV radiation. Force it into the crack with steady pressure. The depth should be almost half the width of the fissure. The sealant will “skin” over the crack and you can cut off any overflow with a sharp tool after it has dried. 

Step 3: If the leak is caused by cracks in the gutter, cover the crack with weatherproofing tape. Make sure the area is dry before you tape it, and apply the tape in overlapping strips. Smooth out all the bubbles under the tape for a long-lasting seal. 

Repairing Sagging Gutters

Step 1: Push your sagging gutter back into its original position because you will have to replace the hangers or maybe re-seat them if the sag isn’t too serious. Remember to maintain the slope that goes toward a downspout: about ½ inch downward slope for every 10 feet of gutter.

Step 2: Mark the gutter for gutter hanger brackets every two feet and drill holes through the gutter apron and into the fascia. 

Step 3: Place each gutter bracket in its place under the front lip of the gutter and secure it in place. Make sure you get brackets that come with screws built in because they’re easier to install and last longer. 

If your gutter is held with spike-and-ferrule hangers, you can simply use a hammer to drive the long spikes into the fascia. If it fits and grabs a position securely, you’re good to go. But you will need a replacement if it doesn’t. 

Step 4: Fill in the old screw holes with a sealant to prevent new leaks. 

Repairing Leaks from the Downspout

Step 1: Use a wire brush to get rid of any loose paint or dust around the damaged area. 

Step 2: Wrap weatherproofing tape around the leaking part and overlap the ends. Keep on wrapping overlapping lengths of tape till the crack is completely covered, then smooth out any air bubbles. 

Step 3: Pour water through the gutter to test if your fix has stopped the leak. If it hasn’t, you might need a replacement. 

Tips to Prevent Leaky Gutters

Keep your gutters in a good shape with the following tips:

  • Install quality leaf guards or mesh over your gutters if your home is surrounded by lots of deciduous trees.
  • Schedule gutter cleaning every spring and fall.
  • Sweep away heavy loads of fallen leaves from the roof to prevent the gutters from clogging or scratching.
  • Inspect the rain gutter regularly for holes, cracks, missing or loose screws, and other damage. It’s better to nip the problem in the bud before it gets your gutters leaking.
  • Keep observing the drainage at the bottom to see if the water is running out smoothly. If there’s a back up instead of easily draining out, remove the downspout base and use a long stick or hose water to dislodge debris or leaf build-up. 

Frequently Asked Questions About Gutter Repair

How Long Do Gutter Sealants Last?

Gutter sealants can last 5-15 years, depending on the weather conditions and maintenance. 

What Is the Best Caulk For Fixing Leaky Gutters?

Butyl rubber caulks, or Butyl-Flex caulks are great for repairing gutters. They adhere quickly, are flexible, and hold up well against hot and cold temperatures. 

How Often Should You Replace Your Gutters?

The time for a gutter replacement depends on weather conditions in your area, your maintenance routine, and the material it’s made from. On average, you will need to replace your rain gutters after 20-25 years. 

When to Call a Professional

DIY-ing your way through every gutter leak won’t always work. Your gutter might need a replacement or maybe the repair job is a little too complicated for you. It’s better to call in a gutter pro and let them make the appropriate assessments, repairs, and/or replacements.

Main Image from Canva Pro.


Farah Nauman

Farah Nauman is a freelance writer and an accountant based in Pakistan. She spends most of her time combating the South Asian heat and being a mom to her three fluffy cats and a dozen little Aloe Veras in her house.