It is the cheapest roof maintenance there is, and the most neglected. A full gutter isn't just a gutter that overflows. It is a trough of water standing against your roof base, your fascia board and your wall, year in, year out.
And I regularly repair the damage that comes from it. Damaged fascia boards, rotten boarding at the roof base, damp patches upstairs.
How often, and when
With trees nearby: twice a year. In late autumn, once the leaves have fallen, and in spring to clear out the winter debris and the first blossom. With a lime tree or a birch outside the door, that is no luxury.
In an open setting: once a year. Late autumn. Even without trees, all sorts of things end up in a gutter: moss from the roof, sand, roof gravel, birds' nests.
After a storm: take a quick look. An autumn storm brings more leaves into a gutter in one night than a whole month does. See
checking the roof after a storm.
With a box gutter: always twice. A built-in box gutter holds more sludge and, when blocked, leaks inwards instead of outwards. See
the zinc box gutter.
“Autumn is the round that counts. A gutter that goes into winter full stands under water for three months.”
Fouad, owner of Astrodak Service
Why autumn is the most important moment
In winter it rains a lot, the temperature hovers around zero and the sun no longer dries anything. A gutter that goes into winter full of sludge stands under water for months. When it freezes, that water expands and puts strain on the zinc, the soldered seams and the gutter brackets. See
ice in the gutter.
Cleaning after the leaves fall and before the first frost is therefore the round with the most effect. Everything you do after that is repairing something you could have prevented.
Have it checked before it becomes a job
Most of the damage I repair was still a small fix a year earlier. Have your roof checked with no obligation and you will know exactly where you stand.
What proper cleaning involves
The gutter emptied and swept out. Not just the big clumps out, but also the fine sludge at the bottom. That sludge is exactly what holds moisture against the zinc.
The outlets cleared. Where the gutter connects to the downpipe is where the real blockage sits. See
a blocked downpipe.
The fall checked. Does the water really run to the downpipe? A gutter that has sagged holds water in one place, and that is the spot that wears through.
The brackets and the fascia board checked. While the ladder is up anyway. Loose brackets and soft timber are a small job now. See
fascia boards and roof edge trim.
Do it yourself or have it done
A gutter at eye level on a shed or an extension you can do yourself, with a sturdy ladder that someone holds. One storey higher, it is a different story: you work with one hand, you lean to the side, and that is exactly how most falls at homes happen.
What you should definitely not do is spray a zinc gutter with high pressure. That can punch through a spot that has worn thin. See
maintaining zinc work.
Preventing it from being so much every year
A leaf guard at the outlet and a grille over the gutter help, but neither is maintenance-free. A grille stops large leaves and lets needles and fine sludge through, and some debris also stays on the grille itself.
Why sweeping out matters more than scooping out
The big clumps of leaves are the visible part, not the harmful part. What attacks the zinc is the fine sludge at the bottom: a layer of rotted leaves, sand and moss that holds moisture against the metal and never dries out.
A gutter that has been scooped out but not swept looks empty from above and still holds that layer. That is why cleaning is only finished when the bottom is clean and the gutter has been flushed through with water, so you can also see whether the fall is still right.
Frequently asked questions about cleaning gutters
