Windows in shower areas are high-risk installations because they involve moving parts and materials not meant for constant water exposure. You cannot simply tile up to a window; you must wrap the entire window opening—jambs, head, and especially the sill—with a bonded, waterproof membrane that integrates with the rest of the shower system. This ensures that any moisture that bypasses the tile is captured and directed back into the shower. The sill, in particular, is critical. It must have a deliberate slope toward the shower interior so that water cannot pool against the window sash or sill plate. Use pre-formed corner seals and manufacturer-recommended waterproofing techniques to ensure the transitions at the window frame are seamless. If you do not create a complete waterproof shell, moisture will eventually get into the framing, leading to rot. If possible, avoid placing windows in the shower entirely; if you must have one, treat it as a dedicated construction project that requires professional-grade waterproofing.
Key considerations
- shower window waterproofing
- waterproof shower window
- window sill slope
- Window
- Waterproofing
- Membrane