How Do You Clear a Blocked Downpipe?

Pick a wet day, or fill a bucket and pour it into the gutter at the outlet. Watch what the pipe does. If water pools in the gutter above the outlet and does not drop, the blockage is at the top. If the water goes down but spills out of a joint halfway, the stoppage is lower and the pressure is forcing it through the seam. If the pipe runs freely but the ground at the bottom floods, the trouble is in the gully or the drain.

Tap along the pipe with your knuckles from the ground. A solid, dull note often marks packed leaves or silt, while a hollow ring means it is clear. A damp patch on the wall is a clue to a leaking joint, and green staining on a brick face below a joint tells the same story.

Keep your feet on the ground wherever you can. Looking from a distance with a torch or a phone camera tells you a good deal, and it avoids a ladder that you do not need. Our page on why gutters overflow helps you decide whether the pipe is the fault or the gutter above it.

The swan neck is the double bend that carries water from the gutter outlet, which sits out beyond the wall, back to the face of the house. Stoppages gather there more than anywhere, because leaves and moss lodge in the tight turn. On a low roof it can be reached from a ladder. On a two-storey house it needs a tower or scaffold, and we would not suggest standing on a ladder to rod it.

Drain rods, or a long flexible cable with a plunger head, can push a blockage down the pipe. Work from the top where you can, because pushing from the bottom packs the debris upwards. Push gently and never force a rod, since a plastic pipe can split at its joints. After the plug moves, flush with a hose and watch the flow.

If the pipe will not clear, taking it apart is often quicker. Most plastic downpipes are held in clips, and a section can be released, emptied and refitted. Cast iron is heavy and brittle, so leave it to a professional. Wear gloves and eye protection, because the contents are decayed leaf matter and can contain droppings.

At the bottom, the downpipe usually discharges into a gully, a small trapped drain with a grating over it. Leaves, silt and grit settle in the trap and the water stands there. Lift the grating, scoop out the sludge with a trowel, and rinse the trap with a hose. That is a plain tidy-up and it often solves the whole thing.

Some downpipes join a pipe underground that takes rainwater away. If water rises in the gully after you have cleared the top and the trap, the underground run is blocked or collapsed. That is a drainage job for a drain firm, not a roofer, and a camera survey is the usual way to find the cause. Our page on where a downpipe should drain explains how the water should leave the house.

Where the water simply sprays across the ground, the soil beside the wall can soften and wash out, and splashing can mark the brickwork. A short run or a shoe at the foot of the pipe sends it away from the wall. We look at this on a survey, and the photos show you where the water ends up.

A blockage that returns has a reason. Overhanging trees, a moss-covered roof and tiles shedding grit all feed the gutter, and everything ends up at the outlet. A strainer in the outlet, sometimes called a balloon guard, stops big debris dropping into the pipe. It must be lifted out and cleaned with the gutter, or it becomes the blockage. Our view on whether gutter guards are worth it sets out where covers help.

Clearing the whole gutter run once or twice a year, usually in late autumn once the leaves have fallen, keeps most of that out. Check the brackets and the fall while you are there, because a gutter that holds water leaves silt behind. Checkatrade's October 2026 table puts gutter work for 15 to 20 metres with three downpipes at £650 to £1,700, but a clear-out is a small job and a quote after a look sets the price.

If the pipe is cracked, leaning, or badly rusted or sagging, replacing one length is cheaper than repeated clearing. A single written total is what we give, and VAT should be stated on it. We cover the wider job on our gutters, soffits and fascias page.