Clear the spouting before the autumn rain

Clear the spouting and flush the downpipes once a year in autumn, after the leaves are down and before the wet months. In Auckland the wet days climb from about eight a month in March to thirteen in May and fifteen in July. Spouting that meets that rain with a summer's leaves and roof grit still in it will overflow, and the water goes where you least want it.

What spouting does

Spouting catches the rain running off the roof and carries it to the downpipes, and the downpipes carry it to the stormwater. When it works you never think about it. Two details are worth knowing.

Spouting should fall gently toward its outlets, so the water drains rather than sits. Water still standing in a run a day after rain means a bracket has dropped or the fall was never right.

Spouting should also be hung so that if it does overflow, the water drops down behind it, past the fascia, rather than back under the roof. That gap is a safety valve, and it only works while the spouting and the gap behind it are clear.

Why autumn

Leaves, moss, seed pods and grit off the roof settle in the spouting over summer, and the deciduous trees drop the rest in autumn. Clear it once they are down and before the steady rain arrives, so the spouting goes into winter empty. Leave it until winter and you are cleaning in the wet, on a slippery ladder, after the damage has started. If big trees overhang the roof, a second clear in spring is worth it.

The early signs

In heavy rain, stand outside and look along the gutter line.

• Water spilling over the front edge while the downpipe below runs weakly. The outlet is blocked.
• Plants growing out of the spouting. Seeds only sprout where wet debris has settled.
• Water standing in a run long after the rain stops.
• Dark streaks or tide marks on the fascia, on the face of the spouting, or on the wall under a joint.
• Drips at the joins and corners.
• A washed-out hollow at the foot of a downpipe. The water is landing on the ground instead of going into the drain.

If this waits

Spouting that overflows every time it rains keeps the fascia wet, and timber that stays wet rots. From the fascia the water finds the soffit and the top of the wall, and from there the ceiling space, where it shows up as a brown stain on a ceiling, often well away from the leak. Water dumped at the base of a wall soaks the ground beside the foundations and ends up under the floor.

The undersides of spouting and fascias are also what roofing makers call unwashed areas. The rain never rinses them, so salt and grime sit there and wear away the finish. A clear is a small job. A new fascia, a soffit or a ceiling repair is carpentry, painting, and sometimes scaffolding.

Houses with internal or box gutters, hidden behind a parapet or inside the roof line, need the most care. When those block, the overflow can go into the building rather than away from it.

Doing it yourself

On a single-storey house with firm, level ground, this is a job many owners can do safely.

• Use a stable ladder, fully opened or properly footed, and stay off the top rungs. Have someone with you.
• Wear gloves. Lift the debris out into a bucket rather than pushing it toward the outlet.
• Flush each downpipe from the top with a hose. The water should come out freely at the bottom.
• Wash the spouting while you are up there. Spouting makers such as Marley ask for a yearly wash with warm soapy water and a soft brush.
• Check where each downpipe ends. It should run into the stormwater. A downpipe emptying into a gully trap is sending rainwater into the wastewater, and Watercare asks owners to check for exactly that.
• Fit outlet strainers if leaves keep reaching the downpipes. Strainers and leaf guards cut down the debris. They do not end the clearing.

If your drinking water comes off the roof into a tank, the spouting is part of your water supply. Clear it more often, keep the leaf screens and the first-flush diverter clean, and cut back any tree hanging over the roof. These are the same steps Taumata Arowai, the drinking water regulator, sets out for roof water supplies.

When to call a professional

Call someone if the house is two storeys, the roof is steep, or the ground under the ladder is soft or sloping. The job is not worth a fall. Call someone too if the spouting sags, pulls away from the fascia, leaks at a join or is rusting through, because those need fixing rather than clearing. A downpipe that will not clear from the top may be blocked underground, and that is a drainlayer's job.

Ask whoever does it to tell you whether the fascia or the soffit is soft, and to send you photos of the spouting before and after. That one sentence from the ladder is worth more than the clean. File the photos and the invoice on your Archive record, so next autumn starts from what this one found. If you would like a name, the Odyssey Network is the trades and suppliers we have worked with and trust.