Plastering Work Tolerances

Plastering Work Tolerances

1. Plaster Thickness

• Thin finishing coats (skim coats): 0.1 mm – 5 mm
• Standard thin coats: 1 mm – 6 mm
• Base coats and multi-layer systems: typically 10 mm – 20 mm per coat, depending on the plaster type and substrate
• Total thickness: generally 12 mm – 20 mm for walls and ceilings

2. Flatness and Surface Regularity

Measured using a 2 m straightedge:

• Maximum deviation: approximately 3 mm – 5 mm depending on the finish class
• High-quality smooth finishes (Annex A, lighting test): stricter requirements, typically ≤ 3 mm over 2 m

3. Corners and Junctions

• Vertical and horizontal tolerances: typically ± 3 mm over 1 m and ± 6 mm over 2 m
• Corner beads must be installed straight and flush, with a maximum deviation of 2 mm

4. Drying Time and Adhesion

• Each coat must be sufficiently cured and dried before applying the next
• Adhesion must comply with the requirements of the selected plaster system

5. Visual Tolerances

• Hairline cracks up to approximately 0.2 mm are generally acceptable
• A uniform colour and texture are expected, although minor variations are permitted

Practical Interpretation

• Standard residential finish: maximum deviation of 5 mm over a 2 m straightedge
• High-quality smooth finish: maximum deviation of 3 mm over a 2 m straightedge
• Total plaster thickness: 12–20 mm depending on the system (local maximum of 25 mm)
• Corners: maximum deviation of 2–3 mm