Moss is blocking your gutters — clearing them alone will not fix it
The most common gutter blockage we clear is not leaves. It is moss, shed off the roof above, packed down into the run and washed into the downpipe outlet where it sets like a plug.
Which is why clearing the gutter without dealing with the roof is a job you repeat every year.
How the cycle works
Moss growing on the tiles loosens naturally in heavy rain, frost and wind. It washes down the pitch, drops into the gutter, and settles at the lowest point — normally the outlet. Water then backs up along the run and over the front edge.
Because the overflow happens in heavy rain, it is easy to miss. The evidence usually appears as a stained band down the elevation, damp at the base of the wall, or a strip of green on the fascia below the overflow point.
Breaking the cycle
- Clear the gutter runs and flow-test the downpipes, so the immediate blockage is genuinely gone.
- Deal with the roof above, because that is where the material is coming from.
- Treat the covering with biocide so shedding slows rather than resuming next winter.
- Check bracket spacing and falls while up there — sagging runs collect debris faster.
What overflowing gutters actually cost
Persistent overflow saturates the elevation below it. On solid walls that shows as internal damp, on cavity walls it shows as staining and green growth outside, and at ground level it undermines paths and beds. None of it is expensive to prevent and all of it is expensive to remedy.
Stop clearing the same gutters every year
Ask us to quote for the roof and the gutters together and break the cycle instead of repeating it.
Sky Scrapers Ltd · info@sky-scrapers.co.uk
Our own photographs
Images from Sky Scrapers Ltd work showing the methods described on this page.
Where this applies locally
Towns where this comes up most often on our patch:
- Gutter & Fascia Cleaning in BedfordBedfordshire · MK40
- Gutter & Fascia Cleaning in KempstonBedfordshire · MK42
- Gutter & Fascia Cleaning in SandyBedfordshire · SG19
- Gutter & Fascia Cleaning in StevenageHertfordshire · SG1
- Gutter & Fascia Cleaning in Leighton BuzzardBedfordshire · LU7
- Why the north-facing slope is always the one covered in mossCommon problem
- Roof and gutter maintenance for landlords and portfolio ownersFor landlords
- Conservatory roofs, frames and box gutters cleaned at low pressureBuilding type
Questions we get asked
Why do my gutters block every year?
Almost always because there is moss on the roof shedding into them. Clearing the gutter treats the symptom; treating the roof treats the cause.
Do you check the downpipes as well?
Yes. We flow-test the downpipes and gullies, because a clear gutter feeding a blocked pipe still overflows.
Can you do the roof and gutters in one visit?
That is the sensible way round — roof first, then gutters, so everything the roof work releases is cleared before we leave.
Is a gutter guard the answer?
Guards help with leaves and hinder with moss, which is finer and packs into the mesh. We would rather deal with the source on the roof.
Bottom line
The gutter is where the problem shows; the roof is where it comes from. Do both, treat the covering, and the annual clear-out becomes a much longer interval.