Waterproof microcement for showers — what B2B buyers should specify

Waterproof microcement can replace tile in shower walls and wet rooms, but only when the whole system is specified. Buyers should not approve a "microcement" quote that lists only the decorative paste. The waterproof result comes from substrate preparation, primer, reinforcement, cementitious coats, sealer choice and curing control.

The complete shower-wall stack

For shower walls, specify the full stack:

1. Stable mineral substrate or existing tile checked for hollow spots.
2. Adhesion primer matched to tile, render or cement board.
3. Fibreglass mesh at stress zones, corners and board joints.
4. Base microcement coat for build and levelling.
5. Finish microcement coat for colour and texture.
6. Two-part PU or water-based matte sealer, with extra coats in direct water zones.
7. Cure window before water exposure.

Questions to ask the supplier

• Is the system waterproof before sealer, after sealer, or only as a full assembled stack?
• Can the supplier provide the primer, mesh, sealer and maintenance note, not just the finish coat?
• What is the minimum cure time before shower use?
• What slip rating is available for shower floors or wet-room floors?
• Can the supplier provide retained sample records and batch numbers for the colour?

Hotel bathroom specification notes

Hotel bathrooms need repeatability more than drama. Ask for a signed sample board, a written sealer schedule, carton labels that separate base / finish / sealer, and a jobsite instruction sheet in the installer language. For rollouts, order all material for one floor or one property from the same batch whenever possible.

CALMURA project pack

For microcement shower projects, CALMURA supplies a system bill of materials, TDS and SDS for each component, sample-board record, recommended coat sequence, sealer note, packing list template and shipment photos before release.