What is Concrete Plywood?
Concrete plywood, also known as concrete formwork plywood or formply, is a specialised engineered wood product designed specifically for concrete construction applications. This material serves as a temporary mould and structural support system for freshly poured concrete during the casting process.
The primary purpose of concrete formwork plywood is to shape and contain wet concrete whilst it cures and hardens. The plywood must withstand significant hydraulic pressure from liquid concrete whilst maintaining dimensional stability and structural integrity throughout the curing period.
Key construction materials include:
- Birch veneers for premium applications
- Poplar for balanced strength and cost
- Spruce and pine veneers for standard projects
The cross-laminated structure alternates wood grain directions between layers, creating enhanced strength properties that resist warping, splitting, and deformation under concrete loads. This engineered approach makes formwork plywood essential for achieving precise concrete dimensions and smooth surface finishes in construction projects.
When you buy formply, you’re investing in a purpose-built material that ensures reliable concrete forming results across residential, commercial, and infrastructure applications.
What are the Types of Concrete Plywood?
There are several types of concrete plywood available, each designed to meet specific requirements in construction projects. Here are the main types:
1. F14 Grade Plywood
F14 grade plywood serves as the standard choice for most concrete formwork applications in Australia. This grade handles moderate structural loads and provides reliable performance for walls, columns, and basic slab work. F14 plywood offers adequate strength for projects requiring standard concrete pressure resistance.
2. F17 Grade Plywood
F17 grade plywood delivers enhanced structural capacity for demanding construction projects. This higher-grade option withstands greater concrete pressures and spans longer distances without additional support. F17 plywood suits heavy-duty applications including high-rise construction and large-span concrete pours.
3. High-Density Overlay (HDO) Plywood
High-Density Overlay (HDO) plywood features a resin-impregnated fibre surface that creates exceptionally smooth concrete finishes. This premium option reduces surface imperfections and minimises the need for post-pour concrete treatment. HDO plywood proves essential for architectural concrete requiring superior visual quality.
4. Film-Faced Plywood
Film-faced plywood incorporates phenolic resin coatings that provide moisture resistance and extended reuse cycles. These coatings protect the wood core from concrete alkalinity whilst maintaining dimensional stability throughout multiple pours.
5. Curved Concrete Form Plywood
Curved concrete form plywood enables complex architectural shapes through specialised bending techniques. This formwork type supports modern design requirements for curved walls, arches, and sculptural concrete elements that standard flat panels cannot achieve.
What is the Difference Between Concrete Plywood and Normal Plywood?
Concrete form plywood vs normal plywood differs primarily in adhesive technology and protective coatings. Standard plywood uses urea-formaldehyde glue that breaks down when exposed to moisture. Concrete plywood employs moisture-resistant glue systems, typically phenol-formaldehyde adhesives that maintain structural integrity under wet conditions.
Surface coating represents the most significant distinction:
- Normal plywood – Raw wood veneer surface prone to moisture absorption and concrete adhesion
- Concrete plywood – Protected by specialised coatings including:
- Medium Density Overlay (MDO) providing smooth release properties
- Phenolic resin films offering chemical resistance
- High-pressure laminated surfaces preventing concrete bonding
These protective layers enable concrete plywood to withstand alkaline concrete chemistry, resist abrasion from aggregate, and release cleanly after curing. The enhanced adhesive system prevents delamination under the pressure and moisture of fresh concrete pours.
What are the Advantages of Concrete Plywood?
Concrete plywood delivers exceptional performance in demanding construction environments. The durability of concrete plywood stems from its engineered construction, featuring waterproof adhesives and reinforced cross-laminated structure that handles pressures exceeding 50 kN/m² from wet concrete without deformation.
The phenolic resin coating creates smooth, non-stick surfaces that produce professional-grade concrete finishes. This eliminates the need for extensive grinding or surface treatments, reducing labour costs and project timelines.
Reusability of formwork plywood provides significant cost benefits. Quality concrete plywood withstands 20-50 uses when properly maintained, compared to standard plywood’s 3-5 uses. The moisture-resistant properties prevent warping and edge swelling, maintaining dimensional stability across multiple pours.
The chemical resistance protects against concrete’s alkaline environment, preventing degradation that compromises structural integrity. This reliability ensures consistent results across large-scale projects where formwork failure could result in costly delays and material waste.
When Should I Use Concrete Plywood?
Concrete formply serves specific construction scenarios where standard formwork materials cannot deliver the required performance. The applications of formply extend across major structural elements requiring precise concrete placement and superior surface finish.
Primary Uses of Concrete Plywood
Walls, columns, and slabs represent the primary use cases for concrete plywood. These structural elements demand formwork that can withstand significant concrete pressure whilst maintaining dimensional accuracy. Vertical applications like walls and columns benefit from the enhanced strength and smooth surface properties of quality formwork materials.
Grade Selection Based on Structural Demands
Grade selection depends on your project’s structural demands:
- F14 grade: Suitable for standard residential and light commercial applications
- F17 grade: Required for heavy-duty commercial projects with higher concrete pressures
Benefits for Specific Architectural Features
Projects involving curved architectural features or exposed concrete finishes particularly benefit from specialised concrete plywood variants, ensuring professional results that meet Australian construction standards.