How to Unblock a Gutter Drain

An overflowing roof gutter is a problem most of us face during downpours. You may dread the thought of having to climb a ladder to unblock a gutter, and the problem may not even be up on the roof.

More often, the downpipe is the cause of the problem, as a mass of leaves and debris collect and clump with the first rainfall. Unblocking a downpipe by yourself should be an easy task, which is why it is worth checking along with the roof gutter. If you have a shared downpipe that is blocked, consult with your neighbour.

Top Downpipe Blockage

Prevent excess debris from blocking the drain grate by placing wood over it before you start.

• If you have a tall and safe enough ladder and you feel capable of climbing it, you can check the entry hole at the end of the gutter.
• Straighten out a coat hanger but leave the hook-end intact.
• For any leaves and twigs that you cannot reach by hand, you can use the hook end of the coat hanger to reach deeper into the pipe.
• You can also send the coat hanger up from the base of the pipe to help pull blockages down.
• Do not worry about getting every small leaf, as you can wash these down later with a bucket of water.

Middle Blockage

You may find that you are unable to reach the blockage at the centre of the downpipe with your coat hanger. Bends and joins in the downpipe will compound this issue and make it even harder to navigate with your coat hanger.

One solution is to disassemble the downpipe to gain greater access, or you can use a flexible drain clearing rod to push the blockage through. Taking the downpipe off the wall will make it easier to unblock, and there is less chance that you will damage it.

You can test to see where the blockage is by tapping the outside of the pipe with your fingernail; you will hear the change in the echo as you tap over a blockage. Once you have found the blockage, you can remove that section of the downpipe.

When you release the pipe clips, you may find that the downpipe does not want to move — you may need to remove more clips and shake the pipe to free it. Once you have the section off, you can push the blockage through with a length of bamboo or a broom handle.

On taking off the section of pipe, it is worth testing the gutter again to see if water runs through the remaining pipes. Often there is more than one blockage, so check before putting everything back together.

Blocked Storm Drain

If you have cleared the gutters, the pipes, and the water is still having trouble making its way off the roof, then check the storm drain for a blockage. Storm drains often get clogged with leaves or even fat if you use the drain to dispose of cooking oil.

If you pour water into the drain, and it still struggles to disappear, then you can try clearing it with a drain pole. In extreme situations, the drain may need to be excavated to fix the problem, and you may need to call in a professional.

Preventing Drain Gutter Blockages

Trees around your home will shed leaves and twigs — prune these back before they have a chance to fall into your gutter. Get a professional to cut back big branches that could harm you or your roof if they were to fall.

A straightforward way of preventing blockages is to stop the debris from being able to enter the pipe in the first place. DIY stores and some garden centres will sell wire or plastic mesh cups that will plug into the entry hole from the gutter to the downpipe.

These mesh cups will catch debris at the top of the gutter — so, in the future, you will not have to dig through the entire downpipe. Older houses may feed the water runoff into an open hopper to guide the water into the downpipe.

For irregular-sized hoppers and entry holes, you can try making a mesh trap by cutting out a section of chicken wire and fitting it over the hole. Then secure the mesh with wire to prevent water, wind, and birds from moving the mesh.

Cast-iron piping is heavy to move around, and it will crack if you drop it on concrete. But a blocked cast-iron pipe can fill with water in the winter and freeze. Ice frozen within the pipe can also cause it to crack. Crack pipes will trap debris; if you spot any cracks during the clearing process, it is better to replace the pipe.