How to unclog a downspout
Fifteen minutes with a hose usually does it. The order you work in matters more than the tools.
- Doing it yourself
- $0–$35
- Typical contractor price
- $100–$250
This job puts you on a ladder
- Set the base one foot out for every four feet of height. Steeper than that and it slides out from under you; shallower and it tips backwards.
- Extend the ladder at least three rungs above the gutter and tie it off, or have someone foot it. Never rest a ladder on the gutter itself — aluminium will fold.
- Keep your hips between the rails. Reaching sideways past the rails is what puts people on the ground; move the ladder instead, however tedious that gets.
- Stay off it in wind, rain, or on wet grass. A ladder on soft ground sinks unevenly as you climb.
- Standing on the top two rungs is how most ladder falls happen. If you cannot reach from the third rung down, the ladder is too short.
Tools
- •Garden hose
- •Plumber's auger (a drain snake) for stubborn blockages
- •Screwdriver for the bracket screws
- •Work gloves
Materials
- •Replacement downspout brackets if yours are corroded
Step by step
Find where the blockage sits
Tap down the length of the downspout with your knuckles. Hollow above, dull below — the change in note is the top of the clog.
Try the hose from the bottom first
Feed the hose up from the bottom opening and turn it on. Pushing the blockage up and out is far easier than driving it further into an elbow.
Watch out: Starting from the top compacts the clog into the bend at the base, which is the one part you cannot reach.
Use an auger if water alone will not shift it
Feed the auger up from the bottom, turning as you go. Work it through, then flush again with the hose to carry the debris out.
Take the elbow off if it still will not clear
The lower elbow traps most blockages and usually comes off with two screws. Clear it on the ground and refit it.
Check the outlet at the top
While you are on the ladder, check the gutter outlet itself. A shingle grit dam builds up right at the opening and re-clogs a downspout you just cleared.
Stop and call someone if
- The downspout runs underground into a drain — that is a drain-clearing job, and forcing an auger into it can break the pipe.
- Water backs up again within days, which usually means the underground line or the municipal connection is the real problem.
Or read more about gutter cleaning.
Common questions
- Why does mine clog every year?
- Usually an overhanging tree plus no outlet guard. A simple strainer at the gutter outlet costs a few dollars and stops most of it — as long as you then remember to clear the strainer.
- Can I use a pressure washer?
- You can, but carefully and from the bottom. A pressure washer aimed down a downspout can blow the seams apart, and on an underground line it can force water back under the foundation.
Last reviewed September 19, 2026. General guidance only — your house, your roof and your local building code are what actually govern the work.