I have been asked to quote on cleaning the external brickwork on a 1930's house that is undergoing major building works.
The problem is that the windows, and there are plenty, are all leaded.
With the new builds I do the only lead is the flashing, and this always changes colour if the acid gets near it. With the amount of windows involved, covering them isn't something I'd choose to do, nor I doubt the homeowner be willing to pay for.
Are the any non-acid solutions that any of you use in such tricky situations?