How to Unblock a Gutter Downpipe From the Ground
By Emergency Plumb,
A blocked downpipe turns every heavy shower into a waterfall down your wall. The good news is that most blockages sit at the bottom of the pipe, where you can reach them without a ladder.
Short answer: Find where the blockage is by tapping the pipe and watching where water stops. Clear the shoe at the bottom by hand, then push a garden hose up the pipe from the bottom on full flow, or use flexible drain rods. If the blockage is at the top by the gutter outlet, it needs access at height, which is a job for someone with the right equipment.
Finding the blockage
In rain, or with a hose running into the gutter, watch the bottom of the downpipe. Little or no water means it is blocked somewhere above. Tap the pipe from the bottom up: a blocked section sounds dull and solid, and an empty one rings hollow. On plastic pipes you can sometimes see the blockage at a joint or a bend.
Clearing it from the ground
- The shoe and the gully. Pull out leaves and silt from the shoe at the bottom and from the gully grate it discharges into. A blocked gully makes a clear downpipe back up too.
- Hose from below. Push a garden hose as far up the pipe as it will go and turn it on fully. Water pushing upwards often dislodges a plug of leaves that has packed down from above.
- Rods. Flexible drain rods, or a downpipe cleaning tool, can be fed up from the bottom to break up the blockage. Work gently around bends.
- A removable bend. Many plastic downpipes have a push-fit bend near the bottom or at the swan neck. Taking it off gives you direct access, and it pushes back on afterwards.
When it needs access at the top
If the blockage is at the gutter outlet or the swan neck under the eaves, clearing it means working at height. HSE’s guidance is that ladders are for low-risk, short-duration tasks and should not automatically be the first choice. On a two-storey house or above, or over a conservatory, it is safer to get the gutters cleared by someone with proper access equipment; see our gutter cleaning service.
Stopping it happening again
Fit a leaf guard or a wire balloon in the gutter outlet, clear gutters in late autumn once the leaves are down, and check the gully grates at the same time. If the water clears from the downpipe but then backs up at the gully, the drain below is blocked instead; see how to unblock an outside drain.
Questions people ask
Can I unblock a downpipe from the ground?
Often, yes. Most downpipe blockages collect at the bottom bend or the shoe where it meets the gully, and those can be reached from the ground. A blockage at the top, where the gutter outlet joins the pipe, needs access at the gutter.
Will a chemical unblocker clear a downpipe?
Rarely. Downpipes block with leaves, moss, silt and birds' nests, which chemical drain unblockers do not dissolve. Water and mechanical clearing work far better, and do not risk damaging plastic or old cast iron pipes.
How do I know if the downpipe or the gutter is blocked?
If the gutter overflows at one end but the downpipe drips or runs only weakly in heavy rain, the downpipe or its outlet is blocked. If the gutter overflows along its length while the downpipe runs freely, the gutter itself is full of debris or sagging.
Why does a blocked downpipe matter?
Water overflowing from the gutter runs down the wall, soaking brickwork and causing damp patches and mould inside. In winter that water can freeze and crack the pipe or the render.
Sources
- Safe use of ladders and stepladders, Health and Safety Executive