U5 – Finishes

U5 – Session 7:
Direct Plaster Practice
Lime Base Coat



Trainees are …

  • able to organize building site, materials and tools for plaster/render
  • aware of health and safety in relation to other workers, building site, machinery, equipment, PPE (personal protective equipment) and of issues specific to working with lime
  • able to explain the structure of a lime plaster/render with its several layers
  • able 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 rlevant theory


  • how and why to create a 1st layer to bond the plaster/render into the straw
  • the structure and composition of lime multilayer plaster/render with their different thickness
  • drying/carbonating timings of the different layers and tending (control of humidity, exposure, ventilation, etc.) procedures to ensure drying/carbonating
  • connection between layers: remove sinter layer, texturize and wet the surface
  • the protection of a drying render from weather conditions
  • the need of having humidity on the wall during drying period


  • Exercises:
    • apply a lime slip by hand or using a mechanical spray
    • apply base layers of lime with or without fibres to achieve an even wall
    • reinforce by applying mesh
    • check the thickness to guarantee bracing function as load bearing material
    • check good execution to guarantee a minimum thickness for fire protection, air tightness, water proof, acoustic performance and rodent and insect protection

Materials/Documents: U5 S7 – Session Plan

Training Time: 1 day