Hi guys
sorry in advance as i know this has been on before recently. but not got a solution yet.
as stated have an office pp tiles did the whole office came up like new, with texatherm but about a 3m2 are in one office has a distinct water mark.
apparently a gutter leaked on adjacent property so it is rain water. we have been back tried cbt, mpower and hwe. dried the same.
what prespray treatment should i try next.
cheers
john