Downpipe Leaking Or Cracked

What's happening?

A downpipe takes rainwater from the gutter outlet to a gully or soakaway. Its joints are push-fit sockets, sometimes with a rubber seal, and its brackets hold it to the wall. Because the water runs down under gravity, not pressure, a properly made joint should stay dry. When water appears at a joint or runs down the wall, something is wrong: the seal has shrunk, hardened or slipped, a blockage lower down is making water back up until it escapes at the joint, the pipe has come loose from the gutter outlet, or it has cracked. Frost, age, knocks from ladders and old cast iron joints that have rusted are the usual reasons for a crack. Water running down the wall soaks the brickwork and shows as damp indoors.

What usually causes it?

• A joint seal that has shrunk, hardened or slipped
• A blockage in the pipe or the gully backing water up to a joint
• A pipe that has come away from the gutter outlet or a bracket that has failed
• A crack from frost, impact, age or sunlight making plastic brittle
• Rusted joints or holes in cast iron or metal downpipe
• A downpipe fitted at an angle that does not allow it to drain

Is it dangerous?

Not directly, but a leaking downpipe soaks one patch of wall, rots the fascia and soffit nearby and can cause damp indoors. A cast iron section that is loose can fall.

Can I fix it myself?

From the ground, pour a little water into the pipe at its lowest joint and watch where it escapes. If water backs up at the bottom, the gully is blocked: clear leaves from the gully and see if the leak stops. A rubber repair sleeve, a clip or epoxy putty can hold a small crack on a low pipe in the short term. Do not climb to reach higher joints and do not clear the gutter: that is a contractor's job.

When should you call a fascia, soffit and guttering installer?

Call a gutter or roofline contractor if the leak is at height, on cast iron, at the top where it meets the gutter, or if the pipe is cracked along its length. Call a drainage contractor if water backs up at the bottom and the gully is not simply blocked with leaves.

What will the fascia, soffit and guttering installer actually do?

• Trace the leak with water and find the joint, crack or blockage
• Clear the pipe and gully so water runs freely
• Replace the seal, re-seat the sockets or fit a repair sleeve
• Replace a cracked section or the pipe if it is brittle or rusted
• Refix the brackets and reconnect the pipe at the gutter outlet

Who fixes this

• Downpipe repair and replacement
• Gutter joint repair

Questions people ask

Sources & References

1. GOV.UK: Approved Document H, drainage and waste disposal
2. HSE: work at height