[joe34]

I went to a house today to quote on cleaning the render . The owner told me when the builders put the render on a waterproof agent was added to it. Has anyone come across this? and does it effect the cleaning? Thanks in advance

[Splash & dash]

Putting waterprofer in cement render isn’t uncommon shouldn’t make the slightest difference to cleaning it

[Kev Martin]

It was probably PVA

[joe34]

Thanks for advise

[chris scott]

What sort of render is it ? What is the waterproofer ? and with what do you propose to clean it with?

[joe34]

 It's k render  but I'm not sure what waterproof agent has gone into the render the customer doesn't know either. I was planning on using sodium Hypochlorite and a surfactant there's some rust on one on one ofthe sides so some oxsilic acid too. What  would you propose I clean it with?

[joe34]

Just follow on from my original post . What other ways are there to clean render?
Do different sorts of render require a different application?  I've been soft washing for a year or so now but still use hypo and a surfactant and  oxsilic acid for rust and run off.  Is there any other options apart from black wash ect

[Smudger]

there are a few but most are spray and walk away type efforts unlike hypo where you get immediate clean

as your using hypo then theres no need for black wash unless you like throwing money away

do a search for others - I think soft wash solutions is one ( similar name to Daz a purple rhino ) from Ireland - they have there place esp if your dealing with hyper sensitive biodegradable freaks

Darran