U5 – Finishes

U5 – Session 4:
Direct Plaster Practice
Clay Base Coat



Trainees are …

  • able to organize building site, materials and tools for plaster/render
  • aware of health and safety correlated to other workers, building site, machinery, equipment, PPE (personal protective equipment) and of issues specific to working with clay
  • able to explain the structure of a clay plaster/render with it’s several layersable to apply the 1st base coat of a multilayer plaster/render
  • able to apply the base “filling layers” to make the wall even
  • able to apply a reinforcement mesh


  • practical exercises at a workshop or building site together with theoretical support


  • how and why to create a 1st layer to stick the plaster/render on the straw
  • the structure and composition of clay multilayer plaster/render with their different thickness
  • drying time of the different layers and ventilation procedures to ensure drying
  • connection between layers: texturize and wet the surface
  • the protection of a drying plaster/render from weather conditions


  • Exercises:
    • to apply a clay slip by hand or using a mechanic spray
    • to apply base layers with clay and straw to achieve an even wall
    • to reinforce by applying mesh
    • to check the thickness to guarantee bracing function as load bearing material
    • to check good execution to guarantee a minimum thickness for working fire protection, air tightness,  water proof, phonic insulation and rodents and insects protection

Materials/Documents: U5 S4 – Session Plan

Training Time: 1 day