What does DIN 18534 regulate?
DIN 18534 specifies requirements for the planning, selection, execution and maintenance of waterproofing for indoor floor and wall surfaces - with sheet, board and liquid applied waterproofing materials. The standard limits the planned accumulation height to ≤ 10 cm (e.g. level-access showers with channels). The selection is based on water exposure classes W0-I to W3-I.
Parts of the standard:
- Part 1 (requirements/planning),
- Part 2 (sheet materials),
- Part 3 (liquid in composite, AIV-F),
- Part 4 (mastic asphalt/asphalt mastic),
- Part 5 (sheet-like in bond, AIV-B),
- Part 6 (sheet-like in bond, AIV-P).
Water exposure classes (interior)
| Class | Description & examples |
|---|---|
| W0-I low | Infrequent exposure to splashing water, e.g. walls outside shower areas, domestic kitchen walls |
| W1-I moderate | Frequent exposure to splash water, e.g. shower area walls in residential buildings, sanitary cells |
| W2-I high | High exposure, e.g. level-access showers (floors), large showers, public bathrooms (wall/floor) |
| W3-I very high | Very frequent/long-lasting exposure, e.g. swimming pool surrounds, sports facility showers, commercial kitchens/laundries |
Waterproofing requirements and permissible substrates/materials increase with the class. W2-I/W3-I generally require moisture-resistant substrates.generally require moisture-resistant substrates.
Types of construction & substrates (short logic)
| Waterproofing types | subfloors |
|---|---|
| AIV-F (Part 3): Liquid in combination with tiles/boards (e.g. reaction resins, crack-bridging MDS) | W0-I/W1-I: moisture-sensitive substrates possible (e.g. gypsum plaster, gypsum/gypsum fiber boards), depending on the system |
| AIV-B (Part 5): Sheet-like in bond (e.g. Waterproofing sheets under tiles) | W2-I/W3-I: only moisture-insensitive substrates (e.g. cement plaster, concrete, cement screed, cement-bonded building boards) |
| AIV-P (Part 6): Board-shaped in composite (e.g. factory-laminated building boards) | |
| Mastic asphalt (Part 4): Floor waterproofing with mastic asphalt/asphalt mastic |
Planning & execution (Essentials)
- Selectsubstrates suitable for the W class (sensitivity, strength, evenness)
- Solvedetail points (tray connection, door thresholds, floor drains, penetrations) according to the system
- Observeaccumulation height ≤ 10 cm; ensure slope to the drain
- Verifylayer thicknesses (for AIV-F); document logs/photos
- Maintenance in accordance with Part 4/manufacturer documents (inspection/repair in the event of damage)
The original standards DIN 18534-1 to -6 and the respective system documents (ETA/abP/ETB, installation instructions) are authoritative.
If there is only minor exposure to splashing water and water-repellent surfaces are used (e.g., painted wall surfaces outside the shower area). Joints/connections must still be protected.
No. For W2‑I/W3‑I, moisture-resistant substrates (e.g., concrete, cement plaster, cement screed) must be used. Observe system approvals.
AIV‑F = liquid-applied waterproofing in composite form; AIV‑B = membrane-shaped in composite form; AIV‑P = panel-shaped in composite form (e.g., laminated building panels). Selection depends on substrate, zone, and W class.
Either connect to the edge using tub edge waterproofing strips or continue the waterproofing layer behind/under the tub (underfloor drainage if necessary) – depending on the design.