BKR / BBV: the Swedish rules for tiling a wet room properly

Ceramic tile is the surface clients judge a bathroom by. But under the Swedish system, tiling is not a decorative trade bolted on at the end — it is a waterproofing trade. The Swedish Ceramic Tile Council (Byggkeramikrådet, BKR) publishes BBV, the trade rules for ceramic tiles in wet rooms, and they govern everything beneath the tile as much as the tile itself. The current edition takes effect in January 2026 and is written against Boverket's building regulations.

Certification is the entry ticket

Under BBV, wet-room tiling is done by certified companies whose staff hold current wet-room certification, kept up through training and audited quality work. The company hands the client a quality document recording what was installed. This is the same logic as the plumbing and waterproofing rules: the standard is enforced through who is allowed to do the work and what they must prove afterwards.

The substrate decides everything

Tiles are only as good as what they sit on, so BBV is strict about the substrate:

• Floor gradient. The floor must fall correctly toward the drain — a recurring focus of the rules, and a common defect when ignored.
• Sound, stable bases. Concrete, lightweight concrete, plaster, filler and screed, and board constructions each have their own requirements for strength, flatness and moisture before work begins.
• The right boards. In board construction, only approved wet-room boards are used, fixed as specified.

If the substrate is uneven, damp or weak, no amount of careful tiling will save it.

Watertightness comes before beauty

BBV treats the watertight membrane as the heart of the system. The rules cover which membrane types are allowed, how the watertight covering kit is applied, and — most importantly — how it is sealed at the vulnerable points:

• Penetrations in floors and walls for pipes and fittings, sealed with the system's collars.
• Transitions between different membrane kits, and between membranes intended for different surface materials, so there is never an unsealed gap.
• WCs with a built-in cistern, a classic weak spot, get specific membrane detailing.

The 2026 edition sharpens several of these areas, including the tile frame, floor gradient, electrical installations in wet rooms, and how construction products connect to the membrane.

Materials and execution

Only suitable adhesives, ceramic tiles and grout are used, matched to the location and the membrane system, and applied per the installation instructions. Grout and tile are water-resistant, not waterproof — they slow water down, while the membrane beneath does the real work. Understanding that hierarchy is what separates a tiler who decorates from one who protects.

Coordinated with the other trades

BBV does not stand alone. It is aligned with the plumbing (Säker Vatten), waterproofing (GVK) and painting (MVK) rules so that, where trades meet — a pipe through a tiled wall, a drain in a tiled floor — the responsibilities and details line up instead of leaving a gap nobody owns.

What M5 brings to Dubai

Here, tiling is often judged purely on the grout lines and the pattern. We judge it on what's underneath: correct fall, a sound substrate, an approved membrane sealed at every penetration and transition, and the right materials installed by people who understand they are building a waterproof surface that happens to be beautiful. The finish you see is the easy part; the system you don't see is what we stake our name on.