Dark patches on exterior wall

[robtiffen]

Hi there. The front wall of my circa 1880 terrace house has develope

small dark patches about 3' up from the floor. I know that the wall ha a damp course put in in 1984, and that this damp course was treate again in 2004. I'm not suire whether the dark patches that hav appeared are damp or not, and I would be really grateful for any advic about this. Could this be residual damp from pre1984?Or could there b aproblem with the plaster? I have checked the plaster on the outside o the wall, and it looks fine

-- robtiffen

[Andrew Gabriel]

You haven't provided enough information. What's "the plaster on the outside of the wall"? Do you mean render, and is it original or something which has been added at some point? What's the decoration on the inside? Why/how was the damp course treated again last year?