Moss on concrete garage roof - clean and coat, or not?

[NorthnotNorth]

NorthnotNorth, good evening.

One discussion I heard of [OK some time ago] was,

Moss growing on an Asbestos Cement roof will hold on to the roof by a small root system.

The discussion went something like if you scrape of the moss, the embedded roots [could ! ! ! ] ??? release Asbestos Fiber into the atmosphere.

Ok that view could be looked at as being ultra cautious, also given the operation is occurring outside, any breeze will dissipate whatever small volume of fibers are released by prizing of the moss?

Ken.

Thanks! I'd heard arguments along those lines, and if I was scraping moss off myself they would convince me to take precautions. I'm less sure how this applies to moss birds have picked off, though!

I know the birds may face some exposure when pecking off the moss, but I'd guess wild birds don't live long enough for mesothelioma to be an issue for them anyway...so the question is more about exposure for people handling the moss after birds have pulled it off. I'd guess that wind, rain etc will take care of any fibres attached to stray lumps of moss?

 

[NorthnotNorth]

Sorry - more exciting roof news... I've noticed that a bit of concrete was knocked off the edge at some point - see picture. Maybe in some of the storms we've had.

It's nowhere that's going to cause a leak, but does this make a difference to roof longevity - or OK to still leave as is? Thanks!

 

[banjodeano]

This kills moss DEAD
https://www.ebay.co.uk/itm/IRON-SUL...e=STRK:MEBIDX:IT&_trksid=p2057872.m2749.l2649

 

[Harry Bloomfield]

Thanks! What makes me cautious about this is reports of problems in strong wind - I live in a very windy spot....

Copper is heavy, fixed at either end, it will not move far.

 

[lostinthelight]

This kills moss DEAD
https://www.ebay.co.uk/itm/IRON-SULPHATE-2kg-99-Technical-Grade-Ferrous-Sulphate-Lawn-Moss-Killer/302422163380?ssPageName=STRK:MEBIDX:IT&_trksid=p2057872.m2749.l2649

And turn the roof orange??

 

[NorthnotNorth]

Thanks - will look again at copper. As in the picture, something has took a piece off the edge of one of the concrete panels. Is this likely to cause problems, or just something I can leave? It's not in a position where it'll cause a leak or anything, assuming it doesn't get worse.

 

[Burnerman]

So long as the rain water drips into the gutter, everything is fine - if it doesn't, time for a patch of some kind.
Regarding metallic copper, the effects of rain wash are absolutely minimal and strictly local to the position of the copper. I've been battling this for years as there is a lot of trees around me and moss growth is heavy......I put some 0.5mm strip copper along the ridge and sat back to watch the results.....effective, but only to the next couple of tiles down and then its as it was before
If you want to clean your roof then wash it when the moss is already saturated - the asbestos fibres won't get airborne but if you are pressure washing, the results are a little aggressive so don't overdo it!
John

 

[NorthnotNorth]

Thanks. The rain should still run into the gutter fine - it was more whether damaging the edge of the concrete means the gap is likely to grow, or it'll just be as strong (or fragile) as it was before...

 

[Burnerman]

It will be fine - likely its just had a knock with a ladder, piece of timber or whatever.
The golden rule.....keep off the roof as much as possible!
John