Summary: Learn how to unblock a downpipe, remove a UPVC downpipe, remove a cast-iron downpipe and prevent a blockage in the downpipe.
When repairing a downpipe, always use a ladder with stand-off brackets or arrange for a helper to support the bottom of the ladder.
Unblocking a downpipe
If the guttering is overflowing, the cause is most likely a blockage in the downpipe or in the swan-necked section at the top of the downpipe. Blockages can be caused by a bird’s nest, a ball or a collection of wet leaves. Another indicator of a blocked downpipe is water leaking from a joint where two sections of downpipe are joined together. This also indicates which section is blocked: it is in the section directly below the leaking join
- Block the bottom of the downpipe with a rag to prevent the debris going down the drain.
- From the top of the ladder use a length of wire to loosen blockages near the top, hooking out the obstruction if possible.
- If the blockage is further down the pipe use a flexible drain rod to probe the downpipe.
- To ensure all the debris has be cleared away return to the top of the downpipe with a hosepipe and flush any remaining debris down the pipe.
- Remove the rag from the bottom of the downpipe and dispose of the loosened debris.
- If you cannot loosen the blockage with a flexible drain rod, you will need to remove the downpipe in sections to gain access to the blockage.
Removing UPVC downpipes
- Starting from the bottom of the downpipe, remove the screws securing the pipe clips to the wall. If your downpipe is secured to the wall by two-part brackets, undo the bolts holding the rings to the back plates but leave the back plates fixed to the wall.
- Work your way up the wall removing sections of pipe until you reach the section with the blockage.
- Probe the blocked section with a flexible drain rod to clear the blockage.
- When the blockage has been cleared, the pipe sections can be fixed back in position.
Removing cast-iron downpipes
- Starting from the bottom of the downpipe, use pliers to remove the pipe nails fixing the integral lugs to the wall.
- Prise rusted lugs away from the wall using a claw hammer and cold chisel.
- Carefully remove the section of pipe from the wall and probe it with a flexible drain rod.
- Work your way up the wall, removing lugs and pulling sections of pipe gently away from the wall until the blockage has been located and cleared.
- When the blockage has been cleared, re-fix the pipe sections to the wall.
Preventing blockages
To prevent future problems with a blocked downpipe, wire or plastic downpipe covers in various sizes are available, which can be fitted over the opening at the top of the downpipe.
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