We have a wonderful stone fireplace, 77 yrs. old. Water does cascade down the front of the stone work, puddles on the stone mantle and into the old oven and fire box. We recently had a cricket installed and flashing redone, but yesterday, with torrential rains and melting snow found that the cricket did not resolve the problem. The water poured in where the ceiling drywall meets the stonework. Now do we need a mason? New crown wash? Can these happy homeowners do these type of repairs ourselves? Is there a mason sealent that will waterproof where there may be cracks not obvious to us?