Killing moss on roof - why do you need to flush ?

[mointainwalker]

Hi

I have a small and growing moss problem on my roof and DIY solutions on the net recommend 50/50 bleach /water or same with vinegar, but also then say flush copiously with water . Why ? I'd prefer not to heave buckets of water onto the roof if unnecessary.

I live in the French Alps and have a "patterned" plastic-covered steel- roof ( pretty common) with panels 1300 mm x 300 mm, so if this flushing is to do with avoiding erosion to the masonry tiles/slates , I imagine I would be fairly safe: also no gardens close-by likely to be affected by run-off.

The moss is not solid fist-sized lumps as may be the case in the UK, but much wispier growths. The roof was new 12 years ago, so it has taken that long for this growth.

My gutters and down-pipes are copper.

Thanks

 

[Burnerman]

I guess bleach would stain the roof, hence the flushing.
For plastic coated steel I'd be more inclined to lightly brush any moss off if you can - any scratching through of the plastic would set the rust away and you don't want that!
Have you considered a chemical patio cleaner? They work to some degree.
John

 

[mointainwalker]

Surprised to see you on here, John. I didn't mention it initially, but the plastic also has inclusions/additions of some kind of "gravel". I can brush the moss off, but that puts me 40+" above the ground for a lot longer than I like and was therefore looking to minimise that time. I have not considered proprietary cleaners because:

a) I'm careful with the bawbees
b) I don't believe they would be much better

 

[^woody^]

Wet and Forget works well on moss Wet & Forget UK - Mould, Lichen & Algae Remover (wetandforget.co.uk)

 

[mointainwalker]

John - I've got another sheet of the roofing material, so I'll make a trial to see if it stains.

Woody. thanks for the suggestion, but not available locally. Any idea what the active ingredient is, as it says "no harmful chemicals" ?

 

[HERTS P&D]

Any idea what the active ingredient is, as it says "no harmful chemicals" ?

Angel tears, Unicorn horn, Eye of Newt and a Jaguars earlobe.

Hope that helps!!

Andy

 

[Mottie]

that puts me 40+" above the ground for a lot longer than I like

Blimey, 40 + inches! You really are afraid of heights………..

 

[mointainwalker]

Ha yes, hadn't seen that! There was however an old fellow in the village - formerly a stone-mason - who was in a wheel-chair for many years and his injury came about when stepping off a plank about 2' up on blocks. Another neighbour walked with great difficulty on crutches for years after falling off his balcony when trying to nudge his satellite-dish that last inch or two.

When you're 5 000' up to start with, those next 40" can be the dodgy ones

 

[HERTS P&D]

And I keep telling the wife that 7" is huge!!

Andy

 

[JohnD]

John - I've got another sheet of the roofing material, so I'll make a trial to see if it stains.

Woody. thanks for the suggestion, but not available locally. Any idea what the active ingredient is, as it says "no harmful chemicals" ?

last time I mentioned wet and forget, somebody said what the chemical was.

A search might find it.

 

[JohnD]

here you are

https://www.diynot.com/diy/threads/green-walls.573906/#post-5001854

wet and forget does not need be be rinsed off IIRC. I bought 5 litres and it will last as long as I do.

 

[^woody^]

Woody. thanks for the suggestion, but not available locally. Any idea what the active ingredient is, as it says "no harmful chemicals" ?

I'd need to have a look on the label in the shed, if there is no info on the website. It must be harmful to moss though! It did mention washing off any over-spray from any plants etc and being safe to pets once dry.

I got mine from Amazon, so they may be able to ship it over to you.

 

[^woody^]

Ha yes, hadn't seen that! There was however an old fellow in the village - formerly a stone-mason - who was in a wheel-chair for many years and his injury came about when stepping off a plank about 2' up on blocks. Another neighbour walked with great difficulty on crutches for years after falling off his balcony when trying to nudge his satellite-dish that last inch or two.

When you're 5 000' up to start with, those next 40" can be the dodgy ones

Don't worry about heights, as it's never the fall that causes injury ..... only the landing.

 

[mointainwalker]

I got mine from Amazon, so they may be able to ship it over to you.

I'm not doing that at the moment as there still seems to be confusion about imports and some locals have been hit with big bills for customs clearance etc and you can imagine trying to fight FedEx to say the goods were under the value limit and trying to get that fee back.

JohnD - Thanks for that information. I've made a note, but will try bleach mixture first.