[Sure Cleaning]

We have been asked to clean two Block Pave Driveways that have already been sealed a  few years ago.  

Is there a chemical or method to use that will remove the sealant. We have tried one a few years ago but the pressure washer did not remove all sealant, just some.

We have a Tech-Clean PT200-21, with a flat surface cleaner and turbo lance.  

Any advice on how to clean these well, would be appreciated.

Thanks

Steve G

[Simon@Pristine Pathways]

Why do you want to remove the sealant?
Simon

[Sure Cleaning]

Hi Simon,
The sealant is already wearing away in some places, also on one of the jobs the homeowner did it themself with gloss sealant and it looks terrible!!

[chris scott]

What sealant is it?

[Sure Cleaning]

Hi Chris,

I don't know what sealant it is, I would say a good quality not water based sealant.

[Simon@Pristine Pathways]

Ask customer if they know or have they got the tin in the shed. The most important thing is to identify it
My motto is if in doubt dont get involved , move on to next job! Thats me chris will have the answer for you!

$imon

[chris scott]

If it's acrylic and not a pu. First wash it ,let it dry and the scrub it with xylene. You wont actually remove it but it will "water it down" till the block absorbs it and it will virtually disappear .
If it is Resiblock or a similar Polyurethane i would walk away from the job and leave it to somebody else.
If you absolutely do want to remove it and it's polyurethane you need to speak to me first.  

Sorry to repeat what  simon  said......  he beat me to it as i was typing !

[Sure Cleaning]

Thanks Chris & Simon,

I have to agree if a job is too much trouble walk away and is probably what I will do. I will try and find out what sealant they used.

So do you guys offer a sealing service and if so how do you re-clean and seal a couple of years later?  Is sealing really a good idea as the drive or patio still gets dirty and still goes green and when pw not all sealant is removed so must be a very time consuming pain job to re-do.

thanks again

Steve

[chris scott]

You should just be able to pressure wash the area and apply new sealant ( assuming it's acrylic). The new seal will "melt" into the original seal giving a uniform seal.

As to whether sealing is a good or bad thing this is open to debate.

If done correctly on a sound block paving surface it's excellent and does what it is supposed to do. These sealers where developed to prevent colour  sand loss,stain resilience, erosion of subbase  etc  
Problems arise for example when the drive is flexing and it breaks the bond formed then the seal fails giving rise to weeds etc. or the seal was applied to wet paviors (block takes 2/3 hot summer days to dry out completely). Imprinted driveways fail because the seal was applied when the surface was too hot and the solvents evaporated before a bond with the substrate could could form .
So sealers themselves do not tend to fail.It is more likely to be a substrate problem or contractor error although they would never admit to it!
Anything left out side will go green ..look at a sheet of glass in a greenhouse. Sealers were not designed to stop substrates going green....although the will help prevent algae and mosses forming.

[BDCS]

Resiblock told me that their sealer would take on a previously sealed drive either pu or acrylic given the drive was abraded prior to resealing. It looks good at first but a couple of months later it goes grey as it starts to delaminate. I soda blasted the whole drive in the end. Sealing is a minefield as even pre-qualified customers expectations are way too high. I swerve sealing telling customers its cheaper to clean every other year - my clean and seal prices start at £12/m

[Kenny83]

How lomg did it take you to soda blast it mate? did you wet blast the soda or dry blast? how big was the drive?

[BDCS]

I have a proper soda blaster and it took almost a day - its almost impossible to see where you have been as you use water to suppress the dust. The job was for a water company who "marked the customers drive" during some works - he was only pulling a fast one and was only after a new drive right from the start - he was a copper off sick and she also was an ex copper who had been pensioned off because she was injured. I think they had shares in a blame claim firm  I got paid and left the copper to sue the water company - he was a merchant banker 

[Kenny83]

lol. nice one, how big was the drive? I'n asking as I thought about getting someone in to soda / sand blast a drive

[BDCS]

Probably 50m but it was years ago - I have swerved these issues since. The soda blaster has sat in the container for ages as well as the wet blaster is a lot less grief to set up and you don't need a road compressor

[Kenny83]

you mean wet blaster as in one of them that attatches on your pressure washer? would you attempt something like stripping a driveway with one of those? they look like a small pencil jet to me. Ive got a drive that needs stripping and looking at the options as it's a bit of a nightmare with paint stripper