Unknown to me, my roof has been leaking for about the past year. This is a 2 story house and due to the incorrect installation of flashing with a new roof the leak seemed to come down on the inside of the brick outside the 2x4s until it came to the floor on the second floor at one point and about half way down the second floor wall at another and then came to inside. The leak has also caused the cement brick to leach white from the roof down to the foudation. I think (hope)the leak is now stopped but my concerns are two: do I have to be concerned with mould in the wall? will the white disappear from the outside of the brick in time or do I need to use muriatic acid on it?
Answer:
As long as that wall has water in it, there will be white salts washing out of it and yes, you will have mould in there. I would give the wall at least a year to dry out before trying the muriatic acid trip.