In this section

Swedish Wet-Room Rules: Waterproof Layers and Floor Falls

BFS 2024:8 sets wet-room duties for waterproof layers, joints, drains and floor falls. Check the project rules and the chosen trade system.

BFS 2024:8, chapter 7 (in force 1 Jul 2025) Clause SE BFS moisture

Transitional projects: check the older-rule eligibility note.

The requirement

BFS 2024:8, chapter 7 sets clear wet-room duties for new buildings:

  • Section 7 requires watertight layers where liquid water is expected, unless needless. Joints, fixings and pipe entries must keep water out. In floors often exposed to liquid water, only drain openings may pierce the layer.
  • Section 8 requires layers that last despite movement, ageing and other stated stresses.
  • Section 9 requires water-repellent finishes for splash, wet cleaning or condensation, unless clearly needless.
  • Section 11 requires drains where needed on floors often exposed to water. Those wet parts must fall towards the drain. No part of a room with a drain may have a reverse fall.

These clauses do not give one slope ratio or shower-wall height. Chapter 12 sets the rules for changes to existing buildings.

Choose and check the whole system

A wet room needs more than a tub of coating. Check the base, layer, joints, pipe seals and drain as one system. Use the plan and the product instructions together. A tile or grout finish alone does not prove that the whole build keeps water out.

Trade schemes can help with these details. GVK covers wet-room systems, including layers beneath ceramic tiles. BBV covers tile work. Säker Vatten covers water and plumbing work. Do not assume that GVK means vinyl only.

Check which scheme and edition the job calls for. Check the contract and any insurer’s terms too. A trade scheme does not replace the BFS duties. This guide does not certify a product or grant scheme approval.

Before the floor is closed

  1. Confirm which set of building rules applies to the job.
  2. Check the wet zones and the layer shown on the plan.
  3. Check the drain, pipe entries, seams and door detail as one system.
  4. Measure the floor falls. Check for low spots that send water away from the drain.
  5. Keep the product records, checks and photos with the job file.

Sources

Related building rules