[BDCS]

Differing views without common ground will never agree ! Some make a living which involves cleaning roofs and some won't, so those that do will carry on collecting the work those that won't.  Nowts as deaf as he who don't want to hear. 
I have learnt from these posts - I will wear waterproofs when shopping in supermarkets :
I won't clean shingles with brick acid.
Why dos'nt someone ask about using a generator with a hot box or chandalier cleaning 
Anyway Merry xmas to those who do it and if you don't bad luck

[Rob_Mac]

I am going to amend any statements I have made on this thread.

I can say that I and any person/s working with me have never caused any damage to a roof that we have cleaned.

I am confident that roofs can be damaged by people that don't know what they are doing.

Fortunately I do know what I am doing and that is why my clients pay me well to look after their portfolios.

Rob

[BDCS]

Yes we seem to agree then

[Blast Away]

Gordon, on your Power Washing page on your website you show roof cleaning. From the limited image example of a roof you've cleaned I'm guessing you haven't done many?
It's not exactly the image your potential customers want to see, unless of course the images of them being brushed aren't too appealing? 

[gordonswindows]

Thank you for that m-clean I didn't realise the link wasn't correct

Our site address is.   www.ithastobegordons.co.uk

The "damage" that may be caused will not become obvious for some time, especially the damp either from the roof itself or worse from the foundations

Please continue with the method you are using although please safe while you are doing it and I will look forward to the "I told you so" moment sometime down the line

Advice is offered it is up to the individual to accept it or not but the great thing about this and other similar forums is we can all gain from others experiences and maybe be big enough to accept that maybe just maybe someone else knows better

How do I know what I am talking about? Am I clever am I smart do I know it all? 

No the reason you should consider my opinion is yes I have caused the damage I am talking about and yes it was costly and no I never thought it could happen to me cos I knew it all I had cleaned hundreds of roofs me I wS an expert NOT

Gordon

[gordonswindows]

That's what happens when you guess BLast Away you get it wrong

These panels were washed with our wfp, safe on a platform not the roof, safe without any leaks and paid weekly to keep them clean

Damn I wish I knew what I was doing

Perhaps our clients enjoy the results they can view on the industry magazine spread where we are photographed receiving our awards

Ever thought less is more and perhaps some people try to hard to show every task they have managed

Gordon

[Blast Away]

It's on your Power Washing page...

[Phild]

Cutting to the chase as this thread is going all over the place:

The Doff System was mentioned earlier (it's not Duff as pointed out) This sytem is often specified for stone cleaning work for decent sized jobs as ..... it's effective and marketed as being safe. We actually have a system and I have used it personally to remove multi-layers of stone and masonry paint from a double fronted, 4 storey 1830 building. Hard work but what a satisfying joy to use. Personally I think it would clean roofs really well but the problem is you would have to use a lance as it's a proper steam cleaner. By this I mean it doesn't chuck out gallons of water and has a variable temperature also you would be moving a cat ladder all over the roof to work from and that means broken tiles on fragile roofs (I am thinking old slates not tiles or modern concrete stuff)

If more than half a dozen people are interested I will do an amateur video of it being used on ............ you tell me what you want it tried on.

PhilD

phil.dixon@newlifecleaning.com

[Rob_Mac]

I would be interested to know what damage was caused, how it was caused, what you did as far as preparation before you created the problem, when the problem materialised and what was the outcome.

Rob

[gordonswindows]

I appreciate why you wish me to share the problems I had and it is all about learning from others experiences but having being so open and honest aout things I really don't fancy airing more of my laundry

The problem was we had done many roof jobs previously without a hitch and as the money was good I asked a well known roofing company if they would let me work with them to train and learn, I spent six weeks with an experienced outfit that did roof cleaning, I don't mean as a side add on service I mean that is what they did and still do. They showed me different techniques equipment and materials and I felt confident in what I was doing.Then had a bit of a "mishap", even though I did it as they showed me.

I went to them for advice on what to do and how to remedy the problem and they said "don't worry that can sometimes happen it's just down to rotten luck" in other words it had and still does happen to them, one of the largest roof cleaning business going, experienced professionals who others aim to be like

I leave you too your roof cleaning and wish nothing but good luck to you but I say it again, power washing roofs is not the best way to clean them.

Gordon

[greencleaning]

Using biodegradable cleaning compounds, we can spray the entire roof surface up to 40 feet high and kill all algae spores as well as loosen built up dirt. After the solution is sprayed on we allow it to work. Once this step is completed, we rinse off the algae and dirt with low pressure from the ground using 200 degree heated water. This method is a proven effective alternative to the traditional high pressure method.

[jaespray]

Using biodegradable cleaning compounds, we can spray the entire roof surface up to 40 feet high and kill all algae spores as well as loosen built up dirt. After the solution is sprayed on we allow it to work. Once this step is completed, we rinse off the algae and dirt with low pressure from the ground using 200 degree heated water. This method is a proven effective alternative to the traditional high pressure method.

i realy think you must be sniffing bio clening compounds thro a 40 foot pipe
there no such thing as low pressure 200 degree heated water (unless you are up mout everest) and there are not many roofs up there
200 degree water is "steam"
steam can only come out effectivly out of a pin jet
if you rinse with a pin jet i bet that roof looks realy nice   "in the dark from a very long distance"
regards john

[jeff68]

There's no evidential proof in either persons statements that pressure washing a roof causes damage (I am whispering.)

The example of wfp on glass is something completely different and bears no relevance. My works are subjected to quite a high degree of inspection. They are often carried out on trading stores with way above the average health and safety procedures.

That seems to be a reply of half finished responses with no substance to back them up.

I have been on your profile to have a look at your website. It doesn't seem to exist (as it backs back onto your profile) - still whispering.

Rob

I used to work at lafarge roofing where we made roof tiles.And I can say that if you force water at high pressure onto the face of a tile which has granuals on then it is true that the life of the tile will be shortened as opposed to  smooth tiles(ie slate and clay based) which has no granuals coating the tiles.So in my experience I would say that the comment on high pressure washing roofs is right but it depends on what tiles you are cleaning.

[Nathanael Jones]

Cleaning smooth tiles or supermarket (metal/plastic) roofs high pressure is fine. On some jobs with tiles unsuitable for high pressure you also find that the home owner has left the roof get too bad & that despite possible damage, high pressure cleaning is the only practical solution.
Personally I prefer chemical cleaners. Sodium percarbonate mentioned before works well on light algae, and degrades quickly making it quite eco friendly. Sodium hypochlorite works better, but does not degrade as quickly & it can "burn" plants & grass so you have to be very careful to soak surrounding areas with water first & rinse everything down after spraying too. Mossgo is slow acting but effective.
All 3 chems though have a problem,.. they kill & remove algae quickly, and moss will die within a couple of days. The dead moss however does not fall of the roof for months without mechanical intervention (Scrubbing with a brush).

My personal conclusion is that in many circumstances, High pressure cleaning is the only effective option. I am constantly on the lookout for a more effective chem though.

[chores hygiene management ltd]

i want to know a bit more about 200 degree water being pumped up onto a roof ?

[Londoner]

I have seen several people cleaning roofs round our way but none of them do it legally, all done working off ladders.
Thats another great minefield that ought to be considered, without opening up the ladders debate that has raged for years on the window cleaning forum.

According to the European Working at Height Directive which has been law in this country since 2006 or 2007. You cannot work off a roof ladder it can only be used for inspection.

[jaespray]

i want to know a bit more about 200 degree water being pumped up onto a roof ?

so do i

[Cliff Horne]

I've been looking at cleaning my own roof for a while now and have recently had a problem with water ingress, so I'm having the roof re-felted and re-battoned while the tiles are on the floor i'm gonna jet wash them, question, should I treat them with anything? they are concrete tiles, by the way it wont cost me much more than having the tiles cleaned in situ 

Regards
Cliff