basement patch crumbling
I recently bought a house and went down to bleach the walls in the basement. It smelled damp down there with no visible water. I took a light weight sprayer to the walls and could hear the patch they used crumbling to the floor. It appears to be sandy in nature and comes off kind of easily.
I want to fix this 'patching' they did and waterproof my 100 yr old ROCK basement. What are the best products to use for this? Remember its a rock basement.