How to Quiet a Noisy Downspout

A downspout that drums, drips, or rattles every time it rains is one of the more maddening small house noises, and the good news is that it is almost always fixable without replacing anything. The sound comes from water hitting a hard, hollow surface inside the pipe. Break that fall, soften the landing, and tighten anything loose, and the downspout goes quiet.

It helps to know what you are actually hearing. A downspout is a thin-walled tube bolted to the side of the house, right next to a bedroom window as often as not. When rain sheets off the roof and pours into it, the water does not glide down in a smooth film. It falls in drops and streams that strike the pipe wall and, especially, the elbows, and the hollow column behind them amplifies every hit like a drum.

First, find which noise you have

Not all downspout noise has the same cause, so match the fix to the sound.

Sound	Most likely cause	First thing to try
Steady drumming or patter in rain	Water free-falling onto pipe and elbows	Rope or foam insert to break the fall
Loud drip-drip between showers	Slow drops landing at an elbow	Soften the elbow, redirect the last trickle
Rattle or tick with no rain	Loose bracket or unsupported pipe	Re-secure straps, add a bracket
Irregular gurgle or glug	Partial clog backing water up	Clear the downspout first

If you are not sure, listen during the next rain and notice whether the noise is a continuous patter (a falling-water problem) or a mechanical rattle (a fastening problem). The two need different fixes.

The rope trick for drumming

The single most effective fix for a drumming downspout is to give the water something to cling to. Drop a length of natural rope, a plastic chain, or a purpose-made downspout insert into the top of the pipe so it hangs down through the run. Instead of free-falling and slapping the metal, the water wicks onto the rope and trickles down its length quietly.

Use a rope thick enough to matter but thin enough to leave plenty of room for flow, secure it at the top so it cannot wash away, and make sure it does not bunch up at an elbow where it could catch debris. This is reversible, costs almost nothing, and often removes the majority of the noise on its own.

Soften the landing at the elbow

Most of the sharpest noise happens where water changes direction, at the top elbow just below the gutter outlet and at the bottom elbow near the ground. These are the spots the falling stream hits hardest.

A foam pipe-insulation sleeve wrapped around the outside of a noisy elbow damps the ring, and a foam insert seated inside the elbow cushions the impact. Some people line the inside of the top elbow with a strip of adhesive foam or rubber so the first impact lands on something soft. The principle is the same throughout: replace a hard, resonant surface with a soft, dead one.

Tighten what is loose

If the noise happens when it is windy or as the day warms and cools, it is mechanical, not water. Downspouts are held to the wall with straps or brackets, and over time these loosen or a lower section pulls away, as covered in our guide to a downspout pulling away from the house.

Walk the run and check every bracket. Add one to any stretch longer than a few feet with no support, since an unsupported span vibrates like a tuning fork. Snug, evenly spaced brackets stop both the rattle and the slow loosening that leads to bigger problems later. While you are there, confirm the whole run is the same profile and size, because mismatched, poorly seated joints both leak and buzz. Our overview of downspout brackets and straps covers correct spacing.

Redirect the splash at the bottom

The last noise many people miss is at ground level, where water leaves the bottom elbow and slaps a splash block, a puddle, or a metal drain. Even a quiet pipe sounds loud if it dumps onto a hard, echoing surface right outside a window.

Extending the discharge, aiming it onto grass or gravel instead of concrete, or fitting a rubber splash guard softens that final sound and moves the water safely away from the foundation at the same time. See how far downspouts should extend for getting the discharge point right.

When noise means something is wrong

Most downspout noise is a nuisance, not a warning. But a new, irregular gurgle can mean water is backing up behind a partial clog, and a sudden change in sound is worth a look. If the downspout has started glugging, check that it is actually draining properly before you soundproof it, because silencing a pipe that is also overflowing just hides a drainage problem.

The bottom line

A noisy downspout is rarely a reason to replace anything. Identify whether you are hearing falling water or loose metal, break the fall with a rope or foam insert, soften the elbows, re-secure the brackets, and cushion the splash at the bottom. Work through those in order and all but the most stubborn downspouts go quiet, no new pipe required.