ISO 4556:2023

Overview

ISO 4556:2023 - Wood raw parquet elements - General characteristics - defines international requirements for hardwood and softwood raw parquet elements used to manufacture parquet strips. The standard covers manufacturing characteristics, geometrical requirements, dimensional tolerances, quality-control methods, sampling and inspection, delivery and packaging, measurement, and marking. It consolidates and updates earlier ISO standards (replacing ISO 3397 and ISO 5321) to provide a consistent framework for suppliers, manufacturers and buyers of raw parquet elements.

Key topics and technical requirements

• Geometrical characteristics: faces and edges must be flat, parallel two-by-two, with sharp arrises; end arrises perpendicular to lateral arrises. Squareness of ends permits a slope not greater than 2%.
• Dimensions & tolerances: separate tolerance tables for softwood and hardwood raw parquet elements define nominal sizes, allowable oversizes and production tolerances. The standard includes safety oversize allowances (for example, a 2 mm safety oversize for width and 20 mm for length noted for hardwoods) and prescribes nominal dimension adjustments based on moisture content.
• Moisture content: at delivery, moisture shall not exceed 20% (hardwood) and 23% (softwood) on a dry mass basis unless otherwise agreed.
• Sampling & inspection: batches are inspected using representative random samples. Sample sizes and permitted rejects are tabulated (e.g., for batches up to 300 pieces → sample of 35 with up to 2 rejects). Measurements must be made at least at two points; flatness is checked against a perfectly flat surface.
• Measurement methods: moisture measured by electrical instruments; if disputed, gravimetric determination following ISO 13061‑1 is used. Dimensional checks require instruments with the prescribed accuracy.
• Designation & marking: required marking includes species symbol (per ISO 2036), dimensions (thickness × width × length in mm), grade and the applicable ISO number (examples in the standard: “QUER – 22 × 50 × 400 – I ISO 4561”).
• Delivery & packaging: bundles should contain same species/dimensions/grade, bound in multiples of ten, and may be palletized or containerized.

Applications & who uses it

ISO 4556:2023 is intended for:

• Wood flooring and parquet manufacturers (raw material specifications)
• Timber and lumber suppliers and exporters (batching, marking, packaging)
• Quality control and inspection personnel (sampling, measurement, acceptance criteria)
• Purchasers, procurement teams and specifiers requiring consistent material standards
• Certification bodies and standards organizations seeking harmonized requirements

Practical applications include contract specifications for raw parquet supply, incoming goods inspection protocols, and production tolerancing for parquet-strip manufacturing.

Related standards

• ISO 4561 - Wood raw parquet elements - Classification
• ISO 2036 - Symbols for marking according to species
• ISO 5323 - Wood flooring and parquet - Vocabulary
• ISO 13061-1 - Moisture determination (gravimetric)
• ISO 17959 - General requirements for solid wood flooring

Keywords: ISO 4556:2023, wood raw parquet elements, parquet tolerances, parquet dimensions, moisture content, sampling and inspection, marking, delivery conditions.