I have a house that I'm about to put up for sale in the autumn. It's a 5 year old new build but the idiot builders didn't properly treat the lead flashing running all the way along the roof, so now I have white and black stains running all down my outside walls.
I want to at least get rid of the stains before selling the property to improve the kerb appeal so can anyone advise of the best way to clean lead flashing stains from rendered walls, and whether the black stains are likely to be caused by algae or something else? I was thinking of gently pressure washing the render and treating with an algae wash but I don't want to make the problem worse.
For reference, the stains look similar to the ones below, but are running all the way from the roof to the ground.
I want to at least get rid of the stains before selling the property to improve the kerb appeal so can anyone advise of the best way to clean lead flashing stains from rendered walls, and whether the black stains are likely to be caused by algae or something else? I was thinking of gently pressure washing the render and treating with an algae wash but I don't want to make the problem worse.
For reference, the stains look similar to the ones below, but are running all the way from the roof to the ground.
