Common Downspout Problems: Causes and Troubleshooting

Like your gutters, your downspouts play a critical role in diverting precipitation away from your home. Functional downspouts are essential in protecting your home and landscape from water damage.

In this blog, Barry Best Seamless Gutters, an experienced provider of gutter installation in Syracuse, NY, shares a comprehensive look common downspout problems, and how to troubleshoot them.

The Importance of Properly Working Downspouts

Downspouts ensure that the rainwater from the gutters is routed into drains, instead of landing near the house perimeter, or worse, near the house’s foundation. Too much water near the foundation can result in the following:

1. Increased Soil Moisture Levels — Pooling rainwater gets absorbed by the soil, which can result in an imbalance in the soil moisture levels. If the house settles unevenly, it could lead to the house gradually—and quite literally—splitting in two. If this happens, you will notice signs such as large cracks in load-bearing walls, uneven flooring and hard-to-open doors and windows.

2. Damage to the Foundation — Most types of foundation are made of concrete. Properly installed house foundation is wrapped in waterproofing material to avoid moisture absorption. However, it is entirely possible for moisture to infiltrate this barrier. Too much moisture can make concrete brittle, resulting in cracks or even greater damage to the foundation.

3. Flooded Basement — Water near the basement can seep through the walls and windows. Whether you have an unfinished or converted basement, you do not want water to linger in the basement. Cleaning up after a flood is bad enough; the sudden increase in basement humidity is even worse. It can lead to mold and mildew growth, as well as damage to the drywall and other structural parts.

These three problems are just a few examples that illustrate the importance of maintaining properly working downspouts. Let’s now take a look at some of common downspout problems.

Clogged Downspouts

Clogged downspouts are caused by the same things that cause clogged gutters. Leaves, debris, animal droppings and loose roofing granules are just a few of the things that can collect in the gutters. If you take protective measures such as regular cleaning and maintenance, as well as installing a gutter protection system like Gutter Helmet®, obstructions within the downspout will be far less common. Unfortunately, such obstructions are easy to miss, since they’re out of sight.

Obstructions within downspouts usually form gradually, similar to accumulated detritus that block kitchen drains. All it takes is an object—a twig, a stiff leaf a clump of animal hair—to be caught in a joint, seam or bend. Smaller pieces of debris will then accumulate over time until a noticeable obstruction has formed. Here are some of the signs of clogged downspouts:

1. Overflowing Water in the Gutters — Overflowing rainwater doesn’t always indicate clogged downspouts. Nevertheless, gutters shouldn’t overflow unless rainfall is unusually heavy. If the gutters turn out to be clean yet are still overflowing, the problem may lie in the downspouts.

2. Leaking Seams — Clogs in the downspout can exert pressure if they occur near the seams. Old and worn-out sealant can be dislodged by the water in the downspout, resulting in “weeping” seams. If your gutters are up for replacement, consider investing in seamless gutters. There are several contractors that offer seamless gutters in Syracuse, NY, Barry Best Seamless Gutters among them.

3. Weak Runoff — If the runoff seems to be a little more than a trickle during moderate rain, something in the gutters must be causing a bottleneck. One way to check for a major blockage is to tap the downspout along its length. Obstructed areas will have a different sound when you tap them.

Downspouts Are Too Narrow

A properly designed gutter system isn’t likely to have undersized downspouts. During the design stage, a skilled gutter contractor will consider several factors before determining the final gutter specifications. Calculating the right gutter size requires accounting for these three factors:

1. Roofing Square Footage — This is the actual roofing area. Often this information is available in the roofing installation plans. If this information is not available, gutter contractors measure the area manually, plane by plane.

2. Roof Pitch Factor — The steeper the roof, the more rainwater it can collect. Gutter and roofing contractors follow standardized factors that correspond with roof pitches. A roof with a 12/12 slope (12 inches of rise for every 12 inches of run) has a factor of 1.3. At the other extreme, roofs with 3/12 or lower have a roof pitch factor of 1.

3. Maximum Rainfall Intensity — This information is provided by the National Weather Service. This denotes the strongest recorded rainfall in the area, measured in inches per hour. Different areas in the same city can have different maximum rainfall intensities.

Say for example a contractor is designing gutters for a house that has a roof with a standard 4/12 pitch, and a total roof area of 1,000 square feet. The corresponding roof pitch factor would be 1.05. Assuming that the local maximum rainfall intensity is 6.5 inches per hour, multiplying all three values would result in an adjusted square footage of 6,825.

The adjusted square footage would now narrow down the gutter size selection to 3X4-inch K-style (rectangular) or 4-inch half-round gutter profile. The downspouts should then be selected according to the gutter size. The gutter contractor will also incorporate other factors such profile, location of the downspouts and distance from the drains.

This illustrates the amount of work that goes into accurately calculating gutter and downspout size. If a gutter system ends up with undersized downspouts, it is either because of a miscalculation during the design stage the downspouts being replaced by aftermarket parts. Another possible reason is that the roof pitch may have changed during roof replacement. In any case, undersized downspouts may need to be replaced by a gutter professional.

Frozen Downspouts

Ice accumulation is a common winter problem that affects downspouts. This happens when there are obstructions in the gutters that slow down the flow of water, or if the mouth of the downspout is blocked by heavy snowfall. Elbows and joints may have standing water that will eventually freeze. If your downspouts are constantly freezing, you can take preemptive action by salting the ground around the downspout. You should also perform pre-winter gutter inspections to make sure that nothing is clogging the downspouts. If your gutter contractor offers a maintenance agreement service, consider signing up for it. Such a plan helps ensure you don’t miss out on maintenance appointments. 

If your gutters happen to have the same problem, consider investing in heated gutter systems Canastota, NY. Helmet Heat® is one such product, and is designed to work with Gutter Helmet. It melts ice and snow in the gutters, keeping them free from the stress caused by the increased weight and pressure of water turning into ice. It also helps keep the gutters clear while helping reduce the required maintenance on both gutters and downspouts.

Call Us for a Free Estimate!

Barry Best Seamless Gutters is your leading provider of Gutter Helmet gutter protection systems, as well as gutter installation services. Give us a call at (315) 697-5000 or fill out our contact form to schedule an appointment.