Just bought a house, it has some moss on the roof, not enough that we actually looked at it and thought “ohh, there’s moss on the roof” but the survey mentioned it.

The only practical problem seems to be that the gutters are blocked (but that’s not lead to any damp anywhere), only noticed because it’s rained twice in the last 48 hours and the newly fitted water butts are bone dry.

Any practical experience of having roof’s cleaned? Internet is full of conflicting advice against jetwashing, or even removing manually with oxygen bleach and a stiff brush and that any painted on coating is a waste of money. But on the other hand that leaving it be will mean the damp moss will destroy the tiles a little more each time it freezes.

The other problem is most of the gutters and downpipes go into the ground as pipes not into a surface drain/grid, so I’m wary of flushing large amounts of soft spongy, swells when wet, moss into them!

What does STW think (other than clean the gutters)?

Scrape it off and the wash it with caustic soda solution.

clean the gutters! no real way of getting rid of this either – it is inherent in the design of the house

although cutting back nearby trees will give light to reduce moss growth

I’ve been told that taking off the moss is likely to cause leaks as you will disturb all the old tiles and because the moss actually plugs smaller cracks and gaps. I just keep my gutters clean.

Cheers, we’ll leave it be then and just unblock the gutters, there’s no overhanging trees, just a couple of small/medium sized ones in the garden.

Would glyophosphate weed killer kill it?
Goggles, super soaker and a ladder…

Goggles, super soaker and a ladder…

I’d been pondering that, or rather an adapted weed sprayer. Only downside is it would mean going up there 2-3 weekends in a row to unblock the drains as the dead moss fell off, assuming it does and doesn’t just stick there.

I’m interested in this because there’s lots of moss clogging the gaps between roof tiles on my extension, especially where a tank overflow dripped for a few weeks before I bent the ballcock arm downwards! I worry that the accumulating moss will begin to force the tiles off the roof sideways.

Got to get up a ladder soon and clear out the gutters so might as well do the roof at the same time. Security is assured by a climbing rope over the ridge, tied to something solid the other side.

I’ve reead that fixing a copper wire to the top of the rook will fo the job….the minerals leach out over time and reduce/prevent the moss growing.

Mine seems to wash into the gutters and down the pipes. Have a filter before the drain heads into the ground, so I just clear that after every heavy rainfall. Doesn’t seem to be doing too much harm. I was told that if you sprinkle bird seed on it the birds will sling most of the moss off the roof. Not actually tried this yet though.

Came across similar in googling, either attach strips of copper across the roof at intervals or no-nails/epoxy/superglue pennies to the tiles at intervals.

Copper is a very effective biocide, it’s used in cooling water systems, one big block and a slight electric current is enough to stop anything growing.

Have the same setup, concrete tiles and gutter into soakaway, and I think I’ve done more damage trying to keep on top of moss growth than the moss has ever done.

Copper wire along the roof works.

think of it as a green roof, and you are being all trendy and environment friendly. A real one would cost a fortune.

moss on yr roof means the air is clean – apparently 20 years ago there would not have been any. My parents have a mossy roof, no overhanging trees but a coastal location so the air is clean. I just clean the gutters – put some wire mesh balls in the tops of downtubes to stop the moss getting in the drains.

As above, I quite like it – funnily enough it is the only house on their road with moss on the roof. Never leaks but I suspect removing it would cause tiles to break/move as it must be heavy.