SERPLYWOOD · CORE GUIDE
GUIDE 08 · ENGINEERING SPECIFICATIONS
18mm Plastic Plywood Selection Criteria & Jobsite Tender Specification Guide
Author: İdris YAĞMAHAN / Mimar (Architect)
Published: 03/04/2026
Read Time: 10 minutes
Category: Specifications & Standards
Quick Technical Specification
Verified Engineering Specs
Nominal Thickness
18.0 mm
Tolerance: ±0.3 mm DIN EN 324-1
Standard Dimensions
1250 × 2500 mm
Sheet Area: 3.125 m²
Sheet Weight
32.5 – 34.5 kg
~10.5 – 11.0 kg/m²
Elasticity Modulus (MOE)
≥ 3,500 MPa
Modulus of Elasticity DIN EN 310
Eğilme Mukavemeti (MOR)
≥ 28.0 MPa
Bending Strength DIN EN 310
Support Joist Spacing
Slabs: 25–30 cm | Walls/Columns: 20–25 cm H20 On-Center
Table of Contents
1. Why 18mm Thickness is the Construction Gold Standard
Across Europe and the Middle East, over 85% of modular slab and wall formwork systems are engineered around 18 mm nominal thickness. This ensures seamless flush alignment with H20 timber beam flanges and steel-framed cassette formwork.
2. Mandatory Mechanical Thresholds
To qualify as an approved structural concrete forming face, polymer boards must verify certified laboratory benchmarks:
- Modulus of Elasticity (MOE): ≥ 3,500 MPa under DIN EN 310.
- Bending Strength (MOR): ≥ 28.0 MPa.
- Surface Hardness: ≥ 70 Shore D.
- Water Absorption: 0.00% after 24h submersion.
3. Sample Jobsite Specification Clause
Section 03 11 00 — Concrete Forming: All slab, column, and wall concrete forming surfaces shall utilize 18.0mm (±0.3mm) cellular polypropylene copolymer shuttering panels. Panels must be 100% moisture-impervious, weigh no more than 35 kg per 1250×2500mm sheet, deliver minimum 50 reuses without surface delamination, and carry manufacturer closed-loop recycling buyback verification.
Download Official 18mm TDS & Specification Sheet
Certified mechanical test certificates, deflection tables, and editable tender clauses in PDF format.
Frequently Asked Questions about 18mm Formwork Specifications
Frequently Asked Questions
Common questions regarding board selection, reuse cycles, technical parameters, and global delivery.
What do hollow, honeycomb, and solid core describe?
They describe the internal cross-sectional geometry of the board. Honeycomb and cellular structures provide lightweight handling, while solid core boards offer different deflection and impact dynamics.
Is SerPlywood a manufacturer brand or a supply/trading brand?
The operating model is specialized polymer formwork procurement, supply, and direct project delivery. Manufacturing and authorized distribution credentials are fully specified within institutional documentation.
Can an 18 mm board be used in all formwork types?
Thickness alone does not determine full suitability. Polymer structure, fresh concrete hydrostatic pressure, support joist spacing, and framing connections must be evaluated within a proper formwork design.
What should the support joist spacing be?
There is no single support spacing applicable to all polymer boards. It must be determined from the manufacturer load-deflection tables and permissible deflection limits (e.g. L/500) for the specific concrete slab thickness.
How does the board behave in hot and cold weather?
Thermopolymers expand in heat and gain rigidity in severe cold. Therefore, an expansion joint gap (1.5 – 2 mm) recommended by the manufacturer should be maintained at board joints.
How many times can plastic formwork boards be reused?
Depending on jobsite practices, handling care, and stripping discipline, boards achieve between 40 and 80+ concrete pours. This is a field-observed operational range under proper maintenance rather than an unconditional guarantee.
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