The Industry Standard for Concrete Formwork
Plyform® concrete forming panels are performance-rated plywood products engineered specifically for concrete formwork. A proprietary designation of APA – The Engineered Wood Association, Plyform® is manufactured by APA member mills with Exterior bond classification adhesives and select wood species veneers to deliver the strength, stiffness, and surface quality required for walls, slabs, columns, and architectural concrete applications. Available in three grades — Plyform Class I, Plyform Class II, and Structural I Plyform — with optional High Density Overlay (HDO) and Medium Density Overlay (MDO) surfaces. Plyform panels are designed for repeated use, consistent concrete finishes, and cost-effective performance on projects of every scale.
Concrete formwork represents close to half the cost of a concrete structure, making panel selection a critical project decision. Plyform concrete forming panels are engineered to deliver the strength, surface quality, and reusability that contractors and specifiers need to keep forming operations on schedule and on budget.
Engineered for High Concrete Pressures: Manufactured with select wood species and Exterior bond classification adhesives to withstand lateral pressures in wall, column, and slab forming applications.
Dimensional Stability Under Forming Conditions: Cross-laminated construction resists warping, edge splitting, and moisture movement through repeated wet-dry forming cycles.
Built for Multiple Reuses: Nonoverlaid panels commonly deliver 5 to 10 reuses, while HDO Plyform achieves 20 to 50 — and up to 200 or more with proper maintenance.
Predictable Concrete Surface Quality: HDO surfaces produce a near-polished finish for architectural concrete; MDO surfaces deliver a smooth matte appearance.
Easy to Fabricate, Strip, and Maintain: Large panel size, light weight, and cross-laminated construction reduce forming labor and resist edge damage during stripping.
Quality Verified by APA: Manufactured to PS 1 tolerances and backed by APA's quality auditing program — reducing the risk of delays and costly rework from off-grade panels.
Plyform® is
one of the most widely used products for concrete formwork, supporting a broad range of forming applications across commercial, infrastructure, and residential concrete construction.
APA-trademarked Plyform panels are engineered for consistent performance and reliable concrete finishes across demanding forming applications, including:
Foundation walls
Retaining walls
Shear walls
Elevator shafts and stairwells
Columns of all sizes and heights
Elevated slab forms
Bridge decks
Post-tensioned concrete decks
Flatwork and grade-level slabs
Exposed concrete walls and feature elements
Gravity arches and curved structures
Textured and patterned concrete finishes
Decorative surfaces requiring precise panel joint control
Large-scale reusable gang form assemblies
Repetitive pour applications on commercial and institutional projects
Modular forming systems for high-efficiency construction
Bridge piers and abutments
Barrier walls
Culverts and drainage structures
Cast-in-place civil concrete elements
Plyform's combination of strength, reusability, and surface quality makes it a proven forming solution for contractors, engineers, and specifiers across virtually every concrete construction sector.
When selecting Plyform® for your concrete forming project, several key attributes — identified in the APA trademark on each panel — determine which product best meets your formwork requirements.
For complete design capacities, engineering calculations, pressure tables, section properties, and technical specifications for concrete formwork, download V345 – Concrete Forming Design/Construction Guide.
V345 – Concrete Forming Design/Construction Guide
Understanding the APA trademark ensures you select Plyform panels that meet the demands of your project.
View Plyform Trademark Example
Plyform Grades – Plyform is available in three grades: Plyform Class I (Group 1 faces for high strength and stiffness), Structural I Plyform (Group 1 species throughout for the highest load capacity), and Plyform Class II (Group 2 or 3 faces suitable for most forming applications).
Overlay Options – HDO Plyform features a hard, thermosetting phenolic resin surface that produces a near-polished concrete finish and supports 20 to 200+ reuses. MDO Plyform provides a smooth matte concrete finish and is typically overlaid on one side. Nonoverlaid B-B and B-C Plyform panels are mill-oiled and commonly achieve 5 to 10 reuses.
Performance Categories – Plyform panels are available in multiple Performance Categories, with 19/32, 5/8, 11/16, 23/32, and 3/4 being the most commonly available. The Performance Category should be compatible with form tie dimensions and selected based on concrete pressure and support spacing requirements.
Bond Classification – All Plyform panels carry an Exterior bond classification, manufactured with moisture-resistant adhesive to withstand the repeated wet-dry cycles of concrete forming operations.
Concrete Pressure Capacity – Maximum recommended pressures on Plyform vary by grade, Performance Category, face grain orientation, and support spacing. Pressure tables in the APA Concrete Forming Design/Construction Guide are based on ACI 347-04 recommendations and account for deflection, bending, and shear limits.
Veneer Grades – Plyform face and back veneers are limited to specific grades to ensure forming performance. B-B Plyform has B-grade veneer on both sides; B-C Plyform has B-grade face and C-grade back. All grades use C or better veneer throughout.
Lumber Framing and Support Design – Plyform panels work as continuous beams spanning between studs, joists, or wales. Framing size and spacing are determined by concrete pressure, Plyform grade, Performance Category, and species of framing lumber. The APA Concrete Forming Design/Construction Guide provides span tables for common framing species, including Douglas-fir, Hem-fir, and Southern Pine.
Concrete pressure and design tables provide maximum recommended pressures (in pounds per square foot) for Plyform panels used in concrete forming applications. These engineering design tools show allowable pressures based on Plyform grade, Performance Category, support spacing, and face grain orientation relative to supports. Unlike basic product specifications, these tables allow engineers and form designers to select the right panel and framing configuration for specific pour conditions, concrete pressures, and finish requirements.
For complete pressure tables, framing span tables, section properties, and design examples, download APA’s Concrete Forming Design/Construction Guide.
V345 – Concrete Forming Design/Construction Guide
Pressure tables calculate maximum recommended loads based on deflection limits (L/360 for architectural concrete, L/270 for general forming), bending strength, rolling shear strength, and span continuity (two, three, or more spans). Tables provide values for multiple support spacings and both face-grain orientations — across supports and parallel to supports. The allowable pressure is the lowest value among deflection, bending, and shear calculations.
Tables are organized by Plyform grade and forming application:
Concrete Pressures – Lateral pressures for column and wall forms based on pour rate, concrete temperature, and ACI PRC-347-14(21) recommendations, with unit weight and chemistry coefficients for mix adjustments
Plyform Class I Pressures – Maximum recommended pressures with face grain across supports and parallel to supports, by Performance Category and support spacing
Structural I Plyform Pressures – Maximum recommended pressures for the highest-capacity grade, with face grain across supports and parallel to supports
Slab Form Design Loads – Minimum design loads accounting for concrete weight plus live loads from workers, equipment, and motorized or nonmotorized buggies
Lumber Framing Spans – Maximum spans for studs, joists, and wales in Douglas-fir, Hem-fir, and Southern Pine, based on equivalent uniform load and number of supports
Values are based on wet plywood stresses adjusted by a concrete setting factor that accounts for duration of load and the rate at which concrete stiffens and begins to carry its own weight. Section properties and allowable stress values are provided for engineers requiring analysis beyond the standard tables.
APA member manufacturers produce Plyform concrete forming panels that meet stringent quality standards verified through APA's rigorous testing and inspection programs. Specifying Plyform panels bearing the APA trademark, manufactured by APA members, ensures you receive products that have been qualified to published performance standards and are backed by ongoing quality assurance testing from a trusted third party.
Manufactured to recognized U.S. and Canadian standards
Subject to ongoing quality assurance and product testing
Produced by companies with proven expertise in engineered wood products
Supported by APA technical resources, evaluation, and industry oversight
Use the APA manufacturer directory to locate member manufacturers and explore the range of concrete forming and other engineered wood products they produce.
Plyform and Overlay Panels: Building Strong Concrete Formwork
APA Engineered Wood Specialist Noah Humberston, PE, breaks down form development, Plyform grades, MDO and HDO overlay options, and the key factors that make concrete forms stable and durable.
The Importance of Code-Compliant Concrete Formwork
This publication describes the importance of adhering to PS 1 plywood specifications to meet the material performance criteria outlined in ACI 318 & ACI 347, as mandated by the IBC
PDF, 2 pages
The ABCs of EWPs: Industrial Applications
48 minutes
Technical Guides - V345
This publication contains grade information, form maintenance recommendations, design information and case studies related to plywood concrete forming
Technical Topic - TT-059
This publication discusses the causes of concrete staining and provides some possible solutions
Technical Topic - TT-029
This publication discusses causes of surface dusting on concrete surfaces when poured against plywood forms and provides tips for prevention and remedial action.
Technical Topic - TT-007
This publication recommends three methods for the installation of a wood floor system over a concrete slab: sleepers, rigid foam or direct.
The APA trademark stamp is a quality and performance mark that verifies an engineered wood product meets recognized industry standards. On Plyform®, the APA trademark identifies the panel class, grade, bond classification, Performance Category, thickness, mill number, applicable product standard, and any overlay designation.
Additional Trademark Examples
For a comprehensive collection of APA Plyform® trademark stamp examples, including Class I and Class II grade variations and overlay, refer to APA Concrete Forming Design/Construction Guide. The guide provides detailed illustrations and explanations to support proper identification and specification.
This means Oiled and Edge Sealed. Concrete form panels are frequently specified to be factory-furnished with a mill-oiled release agent on the surface and the edges sealed.
With reasonable care, HDO Plyform panels will normally produce 20 to 50 reuses or more. Some concrete-forming specialists achieve 200 or more reuses with good results.
OS/EOS needs to be included in the panel specification.
Though not manufactured specifically for concrete forming, grades of plywood other than Plyform have been used for forming when thin panels are needed for curved forms.