Home / Tub Surround Waterproofing

Waterproofing: the Invisible Half

Tile is the pretty 10%. This page is about the dry 90%.

Ask any bidder two questions: 'what board goes behind the tile, and what membrane goes on the board?' If the answer is greenboard and nothing, keep shopping. Here is our specified assembly for New Britain tub surrounds, why each layer exists, and the photos we take mid-job so you never have to take our word for it.

  • Cement board substrate. Won't swell, soften or feed mold when wet.
  • Bonded membrane. Paint-on or sheet membrane over every wet-area square foot.
  • Sealed penetrations. Valves, spouts and fasteners gasketed, not just grouted around.
  • Movement joints. 100% silicone at corners, tub line and ceiling — grout cracks there.
  • Photo documentation. You see the waterproofing before tile covers it. Always.
Materials

Dry-wall system, layer by layer

What goes on New Britain tub walls: the shortlist we actually install.

Ceramic subway 3x6 — Light price, classic face.
Vertical stack
Chevron stripe
Glass mosaic

New Britain notes

In New Britain we photograph every membrane coat with that day's date: New Britain landlords are the highest-volume tile customers in the footprint: surround re-tiles and regrouts between tenants, priced to repeat. Dry walls are a system, not a material — and the system is what our workmanship stands on.

FAQ

Common questions

Q01
How much of my quote is waterproofing?

Roughly $350–$700 of a standard surround: board, membrane, sealants and the labor to do them right. It's the cheapest insurance in the job.

Q02
What waterproofing do you use?

Cement board substrate, bonded membrane over all wet surfaces, sealed fasteners and penetrations, and 100% silicone at every change of plane. Photographed before tile covers it.

Q03
Is greenboard behind tile OK?

No — moisture-resistant drywall still fails under chronic wetting. Most New Britain tear-outs we do are greenboard autopsies. We never tile over it.

Q04
Kerdi, RedGard, Hydro Ban — which is best?

All work when installed to spec; the installer matters more than the brand. We use sheet membrane in showers and paint-on for tub surrounds, per manufacturer coverage rates.