What is tadelakt?
Tadelakt is a traditional Moroccan lime plaster that is compacted and polished with a smooth stone after application and then rubbed with black soap made from olive oil. The soap reacts with the lime to form lime soap (calcium stearate), which makes the surface water-repellent. The result is a seamless, satin-sheen wall with a lively, slightly clouded pattern.
The technique comes from the area around Marrakech, where local lime was first used to seal water cisterns and later for palaces, mosques and hammams. The name is usually linked to an Arabic word for rubbing or kneading. In Europe tadelakt is now used mostly in bathrooms, showers and toilets, and also for basins and furniture.
Tadelakt is not microcement or “béton ciré”, which are cement- or resin-bound finishes. Nor is it stucco lustro, an Italian polished plaster.
In practice
- Use a stable substrate. Masonry, calcium silicate blockwork or a cement- or lime-based base coat are suitable. Substrates that shrink, move or absorb moisture, such as gypsum and timber, cause cracks.
- Finish each area in one go. Tadelakt is applied wet on wet, pressed and polished while the lime sets. Stopping halfway leaves visible joins.
- Let it cure. Lime hardens slowly by taking up carbon dioxide from the air. Only use a new shower after the curing time given by the supplier, often several weeks.
- Clean with soap, not acid. Clean with black soap. Acidic limescale removers, vinegar and abrasives attack the lime. Renew the soap layer regularly in wet areas.
- Expect specialist work. Tadelakt is labour-intensive and costs considerably more than tiling when done by a professional; get several quotes.
Common mistake: trying tadelakt in a shower as your first plastering job. It takes experience with timing and polishing; practise on a sample board first.
Related terms
- Lime
- Decorative plaster
- Plastering
- Stucco lustro
- Tactility
Want to know more about building terms? Visit our knowledge base at fredsdiyplans.com.