We field this question a couple times a week. There is no quick fix for this. If you are troubled with controlling black mildew where the shower floor meets the shower walls and in corners about 10” to 15” off the floor, this indicates trapped water. 

Over the course of time, poorly constructed shower pans become saturated with water, soap scum, organic matter & bacteria – the perfect scenario to encourage mold & mildew. The trapped water has no way to escape and becomes a perpetual resource for mildew. 

No amount of bleach will solve this problem.

If it is not addressed, it’s very possible that water will start to compromise walls in the adjoining room, often a closet that goes un-noticed. Other tell-tale signs: paint bubbling & discoloration on base boards, stains on drywall, musty odors and damp flooring in the adjacent room. Don’t wait to have this checked by a professional. 

We do not recommend removing the shower floor and replacing it: this shortcut compromises the integrity of the shower substrate. Best to bite the bullet, tear out the faulty shower and construct a properly water-proofed shower. 

Atlantic Tile stocks shower water-proofing systems. Staff can explain how they work and recommend local contractors that are familiar with water-proofing systems.