The short answer
Yes, within limits. From the ground you can spray a roof-safe moss killer with a pump sprayer, brush the lowest courses with a telescopic pole, clear the gutters and trim overhanging branches. You should not climb onto the roof, hire a pressure washer or scrape tiles. If moss is thick, high up or growing on fragile roofing, a roofer working from proper access is the safer choice.
What you can reasonably do from the ground
The most useful job is the least dramatic. Keep gutters and downpipes clear, because a gutter that overflows soaks the lowest courses of tiles and gives moss a permanent damp edge. Garden gutter-clearing poles and vacuum attachments let you do this from a ladder footing or a safe stance on the ground.
Next, cut back overhanging trees. Branches shade the covering and drop leaves and seeds onto it, and the moss that follows is nothing more than a plant getting what it needs. Open the roof to sun and wind and the damp problem often eases by itself.
Third, you can treat the roof with a moss killer sprayed from the ground. A pump-action garden sprayer reaches the lower slopes, and a hose-end applicator reaches a little further. Choose a product designed for roofs, mix it exactly to the label and apply it on a dry, still day when no rain is forecast for at least a day or two. Then do nothing for several weeks. The moss turns brown, dies back and falls away on its own.
Why staying off the roof matters
A fall from a roof or a ladder can change a life in a second, and a roof furred with moss is a slippery place to be. Wet moss on tiles or slate behaves like ice under a boot. The surface also hides what lies below it: a cracked tile, a gap at a verge, a battened section that is soft with age.
There is a second risk, which is damage to the roof itself. Concrete tiles lose their surface under a scraper, slate cracks when it is walked on, and a single stepped-on tile can start a leak that costs more than the clean. Our page on cleaning concrete roof tiles shows how thin the protective layer is.
If the roof is on a garage or outbuilding with corrugated cement sheets, do not brush or scrape it at all. Old fibre cement sheeting can contain asbestos, and HSE guidance says a building put up or refurbished before 2000 should be treated as containing asbestos until shown otherwise. Leave that to someone who can identify the material.
Is a pressure washer worth hiring?
This is the point where DIY cleaning most often goes wrong. A rented pressure washer is powerful enough to strip moss quickly, and equally powerful enough to strip the face from concrete tiles, drive water up under the laps and chip old slate. MyBuilder's roof cleaning guide, updated on 21 August 2026, prices pressure washing at £10 to £15 per m², with a caution about delicate tiles. A professional with training and a lower setting can control the risk. Someone using one for the first time from a ladder faces both the height and the force.
The jet also creates a mess. Moss, grit and loosened granules wash into the gutters and downpipes and block them, so a clean on Saturday can bring an overflow on Monday. Our detailed page on pressure washing roofs explains why we steer people away from it.
Are shop-bought treatments safe to use?
Roof moss killers come in several types, and some are gentler than others. Run-off is the main concern. Whatever you spray on the roof ends up in the gutter, then the drain or the soil, so keep it away from ponds, fish and vegetable beds, cover nearby plants, and keep children and pets clear until it has dried. Do not mix products or add household bleach to a commercial one.
Treating the roof does not clean it, either. Dead moss stays in place until the weather moves it, and a roof can look worse for a few weeks before it looks better. Our guide on whether roof moss killer is safe goes through the chemistry and the cautions in more detail.
Remember, too, that anything that falls from the roof lands somewhere: on a path, a car or a conservatory. Move what you can first.
When the moss will keep coming back
A DIY treatment tends to hold for a season or two on a roof in good light and for a shorter time on a north-facing slope under trees. That does not mean the treatment failed. It means the damp, shaded setting that fed the moss has not changed. Our page on whether moss grows back describes how that cycle works and what slows it.
If you find yourself treating the same slope every year, the roof is telling you something. It might be a tile with a rough surface, a lack of airflow or a defect that keeps one section wet. A survey can separate those, and it costs less than repeated rounds of product.
When to call a roofer
Call someone in when the moss is thick enough to lift the tile edges, when it has reached the ridge, when the slope is steep or high, or when the roof is slate, clay or anything old. Call too if you can see slipped tiles, daylight in the loft, or moss growing in the valleys, because cleaning without repairing leaves the weak spot to fail.
We survey the roof from a safe position, tell you whether the roof wants a wash, a repair or simply to be left, and give you the price in writing afterwards. For a visit, phone 01793 626096 or drop us a line via WhatsApp or the site form. The whole range of treatments sits under roof cleaning and moss removal.