ISO 24334:2019

Overview

ISO 24334:2019 specifies a laboratory method to determine the locking strength of mechanically assembled laminate floor covering panels. It covers joints assembled with both vertical and horizontal mechanical locking systems and is also applicable to other mechanically assembled panels (for example, modular multilayer floorings). The test pulls joined panels apart to a defined opening (0.20 mm) or until the joint breaks, and reports locking strength normalized to panel width (kN/m).

Key topics and technical requirements

• Scope & principle: Measures joint resistance by pulling panels apart perpendicular to the lock until 0.20 mm opening or failure.
• Sampling & conditioning: Use five panels (short- and long-side specimens), conditioned to constant mass at (50 ± 5)% RH and (23 ± 2) °C. Constant mass = two weighings 24 h apart within 0.1% mass difference.
• Specimen preparation:
  • Short-side specimens: cut A1 and B1 (length ≥ 110 mm); width rules depend on panel width (gluing or trimming specified).
  • Long-side specimens: cut A2 and B2 (length 200 ± 10 mm; width ≥ 110 mm); glue panels if width < 110 mm.
  • Assemble specimens following manufacturer fitting instructions.
• Apparatus: Calibrated tensile testing machine (force system verified per ISO 7500-1, class 3 for applied range), sliding calliper (0.1 mm), balance (0.1 g), saw, external extensometer or optical measurement (0.01 mm), clamping devices and grippers, calibration plate.
• Testing procedure:
  • 10 N pre-compression, then pull at 0.5 mm/min or 5 mm/min (report speed used).
  • Record force at 0.20 mm opening and force at joint break, plus maximum opening Δs (measure to 0.01 mm).
  • Perform five tests from different panels; repetition tolerance: each result must be within ±20% of the average. Re-test procedures are defined if tolerance exceeded.
• Results & reporting: Average forces divided by average specimen width → locking strength f (kN/m), reported to 0.1 kN/m; Δs reported to 0.01 mm. Test report must include product ID, sample, reference to ISO 24334:2019, traction speed, and results for long and short sides.

Applications

• Flooring manufacturers: product development, quality control, validation of mechanical locking systems.
• Test laboratories & certification bodies: standardized method for performance claims and conformity testing.
• Specifiers, architects and installers: comparative performance data for selection of laminate and modular flooring systems.
• R&D teams: material and profile optimization to increase joint durability and installation reliability.

Related standards

• ISO 7500-1 - calibration and verification of static uniaxial testing machines (tension/compression), referenced for force-measuring system verification.

Keywords: ISO 24334:2019, laminate floor coverings, locking strength, mechanical locking systems, tensile testing, specimen conditioning, kN/m.