[A Foster]

Hi all.

Is there any chemical or pre-treatment for cleaning mainly patios that have a lot of black spots (don't know the technical term)

The black spots seem to be very difficult to remove. I have to put the nozzle very close and go over every square inch of paving to get them clean.

It may be due to my machine being not powerful enough but i've just replaced that for a 13hp honda.

Just wondered if any pre treatment would speed up the job.

Thanks

[BDCS]

The black spots are lichen and hypo will get them off (bleach)

[Blast Away]

Hypo! 

[M W.]

Hypo! 

missed a few spots on the in step.  great befor/after pics.

[A Foster]

 What is hypo?  I keep seeing people refer to it.

IS it a specific cleaning product or just a nickname?

[trevor perry]

What is hypo?  I keep seeing people refer to it.

IS it a specific cleaning product or just a nickname?

 some people call it hypo others chlorus its proper name is sodium hypochlorite but is basically a strong bleach

[A Foster]

OK thanks.

In terms of patios / hard surfaces, is it best to apply and scrub before pressure washing?

[Blast Away]

OK thanks.

In terms of patios / hard surfaces, is it best to apply and scrub before pressure washing?

You won't need to scrub mate. By the time you've been and got a brush from the van after applying it, it will have done the work for you.

[A Foster]

Do you have any websites for suppliers?

Thanks

[Blast Away]

No. My supplier doesn't have a site. Based in Bury. Don't mind telling people what to use. If it helps them do a better job, it gives the industry a better rep. Too many muppets out there doing shiite work.

[dan hughes]

10% bleach

I call it "special chemicals"

Watch out for plants and grass and anything else you don't want killed!!

[Kev Martin]

Another tip as well Pre Wet the stone before ytoyu put the Hypo on it will work even better and faster

Kev Martin
Marble Life Ltd

[Roger Oakley]

Another way to do this is, clean an area of paving first so that is your pre-wet, apply the hypo mix say 3:1 if really bad lichen go 2:1, then clean another area of paving while the mix is dwelling on the first area, after about 15-20 mins the first area should be ready to clean/flush off, then just continue with the rest of what you are doing as above. Another tip, water grass & flower beds before you start any of this, as it will damage plant life if not careful, at this time of year when people have just started putting in tender bedding plants, I will water them first then cover with polythene to stop any spray hitting them, after washing remove polythene, and lightly water plants again, finish clean-up job done.

[mike roberts]

Hi Roger, interesting what you say about plants grass etc ..Hypo will sanatize, obviously it will be watered down, chances are it wont kill plants via direct contact but it can will kill nutrients in the soil. Which in months to come can effect plantlife esp grass, funny enough recently did a  job that was done last yr via another company. Customer assisted we didnt use chems as last time grass died months later around perim of patio it was an easy maint clean so didnt require chems anyhow.
We sheet up as well and try to avoid flushing into soakaways for the same reason vac / pump transfer into mains sewage if poss.

Do you do much graffiti we had a trial of a chem during wk cost around £1 / litre superb results!

[Roger Oakley]

Hi Roger, interesting what you say about plants grass etc ..Hypo will sanatize, obviously it will be watered down, chances are it wont kill plants via direct contact but it can will kill nutrients in the soil. Which in months to come can effect plantlife esp grass, funny enough recently did a  job that was done last yr via another company. Customer assisted we didnt use chems as last time grass died months later around perim of patio it was an easy maint clean so didnt require chems anyhow.
We sheet up as well and try to avoid flushing into soakaways for the same reason vac / pump transfer into mains sewage if poss.

Do you do much graffiti we had a trial of a chem during wk cost around £1 / litre superb results!

I'll always inform clients that even with wetting down edges of lawns (say 1 metre in from paving) that some hypo will most prob. go into the grass depending on the fall of paving etc. You can't always avoid this happening. The grass will grow back, as long as care was taken in the first place, so as not to allow to much chemical to go on to it., common sense really.

Re the graffiti don't really get much call for it these days, I have done it in the past, but we are really just trying to concentrate on 3 areas of cleaning/restoration these days.It's manic as it is.

[Matt Gibson]

Do you do much graffiti we had a trial of a chem during wk cost around £1 / litre superb results!

What chem Mike?

[A Foster]

Am I right in thinking that covering a patio area with the correct hypo mix, all that will be required is a rinse down?

At the moment I remove the black spots just with the pressure washer, but it does take a long time.

Will the hypo also clean all the rest of the dirt?

Any help appreciated.

[Roger Oakley]

Am I right in thinking that covering a patio area with the correct hypo mix, all that will be required is a rinse down?

At the moment I remove the black spots just with the pressure washer, but it does take a long time.

Will the hypo also clean all the rest of the dirt?

Any help appreciated.

Answer is in reply 12 if you read it through.