Removing water seal from a wall..

[iamchris]

I have an external wall that I had rendered and ready to be painted but never got around to.

A little while back my dad sprayed it with Thompsons water seal while doing the rest of the house which means I can't paint it. Any ideas how to get it off so I can paint the wall?

Thanks

 

[foxhole]

Why can't you paint it?

 

[iamchris]

Why can't you paint it?

According to the Thompsons website you can't. I think it will peel off?

https://www.thompsonsweatherproofing.co.uk/faqs/
"No. The hydrophobic properties of Water Seal will negatively affect the adhesion of any paint applied over it."

 

[foxhole]

I have overpainted it without a problem, used a dollop of PVA in the paint and sprayed it on.Do a test area.

 

[Gasguru]

PVA is water soluble and should never be used in damp conditions. SBR is for outside use.

 

[iamchris]

PVA is water soluble and should never be used in damp conditions. SBR is for outside use.

So a drop of SBR in with sandtex masonry paint might do the job?

 

[Gasguru]

I guess you could try it, all I know is that SBR is for waterproof bonding. Have a look at the data sheets or give the manufacturers technical line a ring.
I've only used SBR to make up cement slurrys for waterproofing concrete.