Roof clean method

[pgtips]

Roof lot of moss.
Have sodium hyperchlorite ( dilute 1 to 3 or 4)

Is the right method to apply the sodium hyperchlorite (spray) watering can applied) then gently pressure spray off.
or..
I've seen some people just go straight into pressure washing with no pre treat.

A roofer suggested using the hyperchlorite but he didn't tell me in which order to apply it.

If I put it on first before pressure wash I expect will make it easier to remove moss. Double application but easier and more thorough.

My thoughts were to dilute the hyperchlorite into a bin and use that to feed the power washer and give the roof a once over. Have extension lance, swan neck etc.
Then go over it again with clean water to rinse off. That seems like a much less aggressive approach.

Would that sound sensible?
Thanks in advance,
Pg

 

[HERTS P&D]

Do not pressure wash your roof!

Stiff broom at the most.

Andy

 

[opps]

Does moss damage tiles?

I have never been sure if it causes problems or not.

My gut instinct is that, at a minimum, it will slow down the rate at which the water can fall down the roof, and that it will remain wet for an extended period, but I am only guessing.

 

[foxhole]

Roof lot of moss.
Have sodium hyperchlorite ( dilute 1 to 3 or 4)

Is the right method to apply the sodium hyperchlorite (spray) watering can applied) then gently pressure spray off.
or..
I've seen some people just go straight into pressure washing with no pre treat.

A roofer suggested using the hyperchlorite but he didn't tell me in which order to apply it.

If I put it on first before pressure wash I expect will make it easier to remove moss. Double application but easier and more thorough.

My thoughts were to dilute the hyperchlorite into a bin and use that to feed the power washer and give the roof a once over. Have extension lance, swan neck etc.
Then go over it again with clean water to rinse off. That seems like a much less aggressive approach.

Would that sound sensible?
Thanks in advance,
Pg

Does not require treatment, National roofing association advise against roof cleaning.

 

[Harry Bloomfield]

Would that sound sensible?
Thanks in advance,

The best advice, is not to touch it with pressure washers, or any chemicals. It does little harm, but such methods of removal can do considerable damage. If you must, use a gentle scraper, to remove the loose moss. Bare copper wire, draped along the upper edges of the roof, can help kill it eventually.

 

[bbjc]

Hand scrape it off. Copper doesnt really work. Think the copper we had once upon a time might have but its a lot weaker now. You,d have to put it all over the roof for it to be effective.

Sodium hypo shouldnt really be used in the wrong hands. It has its uses but your average homeowner shouldnt be using it up on a roof. You need ppe and the right equiptment for it. My advise would be too just concentrate on getting the moss off if its safe access up on the roof anyway. That alone should make a big difference.

Moss is bad for a roof. I still dont get why most roofers disagree with that. It will degrade your roof quicker. Holds a lot of water. Slows the run of water off your roof etc and can cause tile damage and leaks if its allowed to get bad enough.

Not talking about a small amount of moss. But nowadays every other job i go to has copious amounts of moss on them. An amount that does degrade your roof quicker and can end up causing problems.

Pressure washers have caused untold damage of roofs up and down the country. Mainly because people have used 3000 psi turbo nozzles on tiles and ridge tiles etc. Degrades the pointing of ridge tiles. Breaks some tiles that they more often that not dont replace.

A tile can take a pressure washer.....but it has to be a suitable pressure and the ridges need to be wired brushed at worst.

The tile coating that people claim comes off....is long gone before a pressure washer reaches that roof.

Again tho a pressure washer has no real place up on a roof imo. Dangerous enough place without hoses and pressure etc. I m not sure a homeowner has a place up on a roof either tbh.

Get a price from the roofer that told you about the hypochlorite.

Dont feed your pressure washer with sodium hypochlorite. Will break it.

 

[Harry Bloomfield]

Hand scrape it off. Copper doesnt really work. Think the copper we had once upon a time might have but its a lot weaker now. You,d have to put it all over the roof for it to be effective.

Pure copper, is pure copper, it doesn't get stronger or weaker. My garage roof used to choke up with moss, I cured that problem using several runs of bare copper wire across the high point, so that the copper sulphate would wash down.

Moss is bad for a roof. I still dont get why most roofers disagree with that. It will degrade your roof quicker. Holds a lot of water. Slows the run of water off your roof etc and can cause tile damage and leaks if its allowed to get bad enough.

That’s because the cure of mechanical, or chemical removal, is usually more damaging than simply ignoring the moss. There are an awful lot unskilled people, offering a moss removal service, and countless reports of damage as a result.

 

[bbjc]

Pure copper, is pure copper, it doesn't get stronger or weaker. My garage roof used to choke up with moss, I cured that problem using several runs of bare copper wire across the high point, so that the copper sulphate would wash down.



That’s because the cure of mechanical, or chemical removal, is usually more damaging than simply ignoring the moss. There are an awful lot unskilled people, offering a moss removal service, and countless reports of damage as a result.

Someone once told me that about the copper. That the stuff we,re getting has less copper content than the old stuff. Probably eu regulations or something like that. Might not be accurate tho.

I,ve seen lots of roofs with copper on the ridge laden with moss. Its usually only really effective for a course or two below. Its never really been effective even tho roofers always advise it. I m willing to bet if the fella puts copper across the ridge it will be ineffective at getting the roof moss free.

You,d need to cover your roof with the copper.

Their probably is a lot of unskilled people offering a moss removal service as their is a lot of unskilled people offering say a flat roof service or a pitched roof service. It doesnt necessarily mean that its bad practise. Just bad workmanship.

Scrape the roof. Apply or dont apply a chemical. I,d advise the fella against the chemical. Only because of a lack of experience/equiptment.

Roof tiles can take a good scape without damage. Wasting your time attempting to give it a gentle brush down.

The tile coating is long gone by the time moss has got a hold of it.

Moss roofs are imo a total mess. Sometimes it adds character to a property. More often that not tho its a problem customers want to get rid of. Minly because it looks unsightly but it often does cause problems longer term. Silly to suggest a roof full of moss isnt causing problems. Half my customers atm...have front and back gardens full of moss coming from the roof. Its blocking gutters up. We,re hitting a point its time to start getting rid before it causes more damage on a roof.

I,ve done my own roof anyway. Came up like a new roof. Not one tile damaged either.

 

[pgtips]

Thank you for all the replies. Up until quite recently I wasn't bothered about moss but what I find is it holds the water like a sponge and seems to have gone mad recently, has got out of hand.

This is the view from kitchen window of the front room roof.

 

[opps]

Wow! That is a lot of moss.

As a Londoner, I seldom saw roof moss as a kid. Here in the big smoke, I would guess it has only been about 30/40ish years since I first saw lichen on a roof tile in London.