Why Are My Gutters Overflowing? A Comprehensive Guide

Overflowing Gutters in rain

Do you walk out into the rain and find yourself hit with an unexpected shower from your gutter system? Although you could save on your water bill this way, most people don’t find it desirable to wash their hair in gutter water. If this is happening, chances are you have one (or multiple) gutters overflowing.

Unfortunately, like most household problems, there isn’t one single cause for gutters overflowing. With this in mind, we’ve assembled a comprehensive diagnostic guide for homeowners.

After all, there’s no need to spend lots of money on repairs or gutter accessories that MIGHT fix the issue. Instead, use this guide to pinpoint the problem. Then you can then find the best, most cost-effective solution for your overflowing gutters.

Still need help after reading this guide? Click here to schedule a free gutter inspection!

Top 10 Reasons for Gutters Overflowing

Dirty Gutters

1. The gutters are dirty

Undeniably the easiest problem and easiest solution. If you have clogged gutters, the water can’t flow through them and down the downspouts.

No flow = Overflowing Gutters.

How do you determine if your gutters are clogged?

If you have a ladder or second-story window (a selfie stick works in a pinch ;)), you can check to see if your gutters are clogged.

Pro tip: If the debris in your gutters is really wet, that’s a good sign that the debris is causing the blockage and gutter overflow.


There are a few solutions. The quickest but most short-term solution is to clean your gutters. Depending on your tree coverage, you should clean your gutters 2-4 times a year.

However, for a more long-term solution, consider gutter guards. Although the gutter guards are not maintenance-free, they do significantly reduce maintenance.

2. The gutters are too small

If you have a large roof, then it catches more water that needs to drain into the gutter system. What’s more, if you live in North Carolina, then your house gets hit with a lot of rain. As a result, your gutters naturally need to hold more water during downpours.

So it goes to show: if your gutters are too small, they’ll fill up too quickly and overflow during heavy rains.

Typically older homes or new construction properties have 5” gutters. 5” gutters can work well for smaller roofs or areas with dryer climates. In any other scenario, it may be wise to consider 6” gutters.

6” gutters can better catch water flowing at high speeds since they are physically wide. Not to mention they can hold 40% more water than 5” gutters.

How do you know if you need larger gutters? One key sign is if your gutters overflow even when there is no debris clogging them. In other cases, you may need 6” gutters if you have large roof valleys.


The solution is undoubtedly a straightforward one: upgrade your gutters.

3. You have too much water flowing to one area

When your roof has a large valley, that means a lot of water will flow into one spot on the gutters. Ideally, you want the roof water runoff to distribute evenly so no one gutter section gets overwhelmed.

To illustrate, imagine trying to use a funnel to sift flour while baking. A funnel will only send the flour to one spot, while a sifter will evenly distribute it wherever you need it to go.

Your roof valleys act like funnels that lead the water to one spot. Chances are, that spot isn’t prepared to handle so much water. Consequently, the gutter will fill up and overflow before the water has time to drain properly.

  1. Hire a roofer to install a rain diverter. This helps “split up” the water to divert some of it to another section of the roof.
  2. Hire a gutter company to install a splash guard. As the water flows to one spot, the splash guard acts as a barrier to catch the water that might slip over the edge.
  3. If you have smaller gutters but don’t want to invest in a full 6” system, replace part of your system with 6” gutters. In fact, we’ve had many homeowners choose to install 6” gutters on a single portion of their property instead of the whole house.

4. The gutters are improperly pitched

The gutter pitch is the angle the gutter sits at to ensure the water flows toward the downspout. If your gutters are not pitched properly, the water could pool in the center of the gutter run. Otherwise, it might flow toward an end cap that has no downspout section. There are even instances where the pitch is too steep, causing the water to flow toward the downspout too quickly.


Hire a gutter contractor to inspect and repitch your gutter(s). To do this, the gutter technician will unscrew the gutter brackets. Next, they will measure out the proper pitch for the roof. Finally, they will reattach the gutter with the brackets in the proper position.

Luckily, this is a fairly inexpensive repair. Unless there is rotted fascia that needs replacement, you are only paying for the service fee, no materials.

5. Your gutter is loose

If your gutter is coming loose from the fascia, it might sag forward. This causes water to spill over like a tilted water glass.

To determine why your gutter is loose, you’ll want an expert to take a look. There are a few potential causes for a loose gutter: your gutter system or fascia is old, the brackets are loose, or there are too few brackets.


If your gutter is loose because it is old, then you’ll need to replace it. However, if it is loose because of fascia rot, you might be able to replace the fascia and reuse the gutter. Otherwise, if the issue is related to the brackets (The clips that secure the gutters to the fascia), the fix is as simple as securing or adding brackets.

6. The underground drains are clogged

Did you know that your underground gutter drainage system can become clogged? If there is a clog in your drainage system, then the water has nowhere to go out of the downspout.

How to tell if your drainage system is clogged
  1. Plants are growing out of the entry point.
  2. Water overflows out of it.
  3. Water pools around the drain.
  4. Your basement is leaking near the drain.

Hire a landscaping specialist to clear out the drains for you. Also, consider adding these to your downspouts to keep debris from flowing through the downspouts into the drains.

7. Your gutter guards are dirty

You might be thinking, “I have gutter guards, so I don’t need to clean my gutters.” Remember that gutter guards are maintenance reducers, not maintenance removers.


Your gutter system still needs a roof/gutter blow-off at least once a year. This ensures that debris doesn’t build up on your roof or on top of your gutter guards.

Thankfully, if your house gets a nice breeze, the wind might do this for you. In rare circumstances, you might have sap build up inside the holes of mesh gutter guards. In these instances, you’ll want to invest in a gutter cleaning wand to spray your gutter guards clean.

8. You don’t have enough gutters

Perhaps you simply don’t have enough gutters. Sometimes a property only has gutters on part of the house. Other times, a property doesn’t have enough downspouts. In some instances, you might have long gutter runs that bend around corners without a downspout at the corner. Ideally, these areas should have individual gutter runs with their own downspouts.


Have a gutter technician inspect the layout of your gutter system. They will be able to recommend if your system needs adjusting or additional downspouts.

9. Your downspouts are clogged

Just like your gutter runs, debris can also build up in your downspouts. Rainwater often carries debris from the gutters down through the downspout. Sometimes, this helps naturally clean out your gutters. In other scenarios, if there is just too much debris, it will clog your gutters. The downspout turns into a clogged pipe, causing water backup.


Carefully use a blower to blow down the top of the downspout to clear out the debris. If you have underground pipes, be sure to disconnect them first. If you have the smaller 2×3 downspouts, consider upgrading to larger 3×4 downspouts.

10. The gutters overflowing are installed incorrectly

Do your gutters sit too far below the roofline? Does water pass your gutters, not into them? One potential cause for this is an overall improper gutter installation. Your gutters need to sit just under the shingle edge in order to easily catch flowing water.


The solution for this is similar to that of repitching gutters. You’ll want to hire a gutter specialist to remove and properly reinstall the gutter run so it sits properly under the roofline.

Remember, there is no need to stress out. Just because these are all potential problems does not mean your house has all these problems. Use this guide to pinpoint the cause, and call in the experts for the fix.

We hope this becomes a helpful resource for you as you take care of your home and diagnose your overflowing gutters. And we hope any problem you have is a quick and easy fix!

Want to make your gutters last longer? Check out our post on that here.

Need a specialist’s assessment? Contact Quality Seamless Gutters for a free gutter inspection, diagnosis, and estimate! As a local, family-owned company based in Apex, we are here to help you solve any gutter issues you might be experiencing.

Serving Apex, Cary, Raleigh, Durham, Chapel Hill, and surrounding areas.