Shower Not Draining Properly: Repair or Rebuild?

A shower that's slow to drain has three possible causes: a blocked waste, a poorly falling base, or a compromised base structure. Each has a different fix scope.

Blocked waste is the easiest and cheapest. Hair, soap and product build up in the waste trap and slow the drain. A drain clearer or a physical clean-out usually fixes it. This isn't a repair job — it's maintenance.

Poor fall is a base-installation issue. If the base doesn't fall consistently toward the drain, water pools in the low spots. On an existing shower, poor fall is very hard to correct without rebuilding the base — the falls are set at the substrate level, not the tile level.

Compromised base structure is the most serious. If the base has settled or cracked, water doesn't just pool — it starts finding its way through the base into the sub-floor. This usually needs a base rebuild rather than a repair.

The pooling pattern usually tells the story. Pooling that clears within a few minutes is drainage/fall — usually maintenance or a live-with-it situation. Pooling that doesn't clear is a base problem and worth an assessment.