We are in the process of building a new house, but a leak at the chimney has us at a standstill. About the only time it leaks is during a hard driving rain. The brick is General Shale's Jefferson Wade Tudor and I've been told since it was laid that it is a very porous brick. The chimney has been treated with ChimneySaver and the crown has been coated with their brushable Crown Sealant. The chimney is in the ridge of the roof and is double flashed, could the water be going behind the flashing? I'm at wits end and am about to put a clearcoat waterproofer on it. Anyone have a solid reason why I shouldn't or a product they'd recommend? TIA!!!!!!