ILPA - Technical Glossary for Formwork Panels

FUNDAMENTAL TERMS

Formwork. A temporary structure used in construction to contain fresh concrete and give it the desired shape during the hardening phase. Once the concrete has reached the required strength, the formwork is removed (stripped). Formwork can be made of wood, metal or composite materials.

Formwork Panel. A flat element that forms the contact surface between the formwork and the concrete. It determines the quality of the surface finish of the pour and must withstand hydrostatic pressure, abrasion and the chemical agents in concrete. ILPA has been manufacturing formwork panels since 1978.

Reinforced Concrete. A composite material obtained by combining concrete (cement, water, aggregates) with steel reinforcement. Formwork serves to contain the fresh concrete until it hardens, after which the steel reinforcement provides the tensile strength of the structure.

Composite Panel. A panel made of different materials combined to achieve superior performance compared to the individual components. In the formwork industry, it typically refers to a panel with a wood core and a plastic surface coating, such as ILPA's STRATO-STOCK®.

Reuse Cycle. Each single use of a formwork panel – from assembly to stripping. The number of achievable cycles determines the cost-effectiveness and sustainability of the panel. ILPA composite panels achieve a significantly higher number of cycles compared to traditional panels.

MATERIALS AND COMPONENTS

Spruce (Picea abies). A softwood widely used in the formwork industry for its lightness, workability and good strength-to-weight ratio. It is the base material for three-ply panels and the core of composite panels such as FIR-STOCK®.

Birch (Betula). A hardwood characterised by high density and hardness. Used in the production of high-performance plywood for formwork applications requiring particular mechanical strength and very smooth surfaces.

Plywood. A panel obtained by bonding multiple thin layers of wood (veneers or rotary-cut sheets) with the grain oriented in alternating directions. This cross-laminated structure provides dimensional stability and uniform mechanical strength in all directions.

Three-Ply Panel. A panel consisting of three layers of solid wood battens bonded with cross-oriented grain. Typically made of spruce, it represents the traditional solution for formwork. ILPA produces it as Cassero.

Phenolic Glue. A thermosetting adhesive based on phenolic resins, used for bonding the layers in formwork panels. It provides resistance to moisture and temperature, which are essential for use on construction sites.

COATINGS AND SURFACE TREATMENTS

Polyolefins. A family of thermoplastic polymers (polyethylene, polypropylene) used as surface coating on ILPA composite panels. They offer excellent abrasion resistance, waterproofing, chemical inertness and ease of release from concrete. Technology patented by ILPA in 1994 with STRATO-STOCK®.

Phenolic Film. A traditional coating applied to plywood panels, obtained from the polymerisation of phenolic resins. It provides basic protection against moisture but has limited resistance to abrasion and nailing compared to polyolefin coatings.

Melamine. A thermosetting resin used as a surface treatment for three-ply panels. It increases resistance to abrasion and moisture compared to untreated wood but offers lower performance than polyolefin plastic coatings.

Polyurethane (PU). A polymer used by ILPA for the perimeter protection of PUR-STOCK® panels. Injected at high pressure along the panel edges, it completely seals the cross-sections of the wood, preventing moisture infiltration – the main cause of panel deterioration on construction sites.

Release Agent. A product applied to the panel surface before pouring to facilitate release from the hardened concrete. Panels with polyolefin coating require smaller quantities of release agent compared to traditional panels.

PROCESSES AND TECHNIQUES

Formwork Assembly. The set of operations for assembling, positioning and fixing formwork on site before the concrete pour. It includes panel preparation, application of release agent and assembly of the formwork system.

Concrete Pouring. The operation of casting fresh concrete into the formwork. During pouring, the panels are subjected to the hydrostatic pressure of the concrete and the vibrations used to compact the material and eliminate air bubbles.

Stripping. The removal of the formwork after the concrete has reached the required mechanical strength. A quality panel allows easy stripping without damaging the surface of the pour or the panel itself.

Hydrostatic Pressure. The pressure exerted by fresh concrete on the formwork walls. It increases with the height of the pour and depends on the filling speed and temperature. Panels must be designed to withstand this pressure without deformation.

Concrete Surface Finish. The aesthetic and functional quality of the concrete surface after stripping. It depends directly on the quality and condition of the panel. Composite panels with plastic coating ensure smoother and more uniform surfaces.

CERTIFICATIONS AND STANDARDS

FSC® (Forest Stewardship Council). An international forest certification system that guarantees responsible forest management according to ecological, social and economic criteria. The Chain of Custody certification ensures the traceability of wood from the forest to the finished product. ILPA exclusively uses FSC® certified wood.

PEFC™ (Programme for the Endorsement of Forest Certification). The world's largest forest certification system by certified area. Based on the mutual recognition of national certifications, it guarantees sustainable forest management. ILPA is also PEFC™ certified.

REACH. European regulation (EC No 1907/2006) on the registration, evaluation, authorisation and restriction of chemicals. It ensures the protection of human health and the environment. All ILPA products comply with the REACH regulation.

EUTR (EU Timber Regulation). A European Union regulation that prohibits the placing of illegally harvested timber on the market. It requires operators to exercise due diligence to ensure the legality of their supply sources.

Embodied Energy. The total energy required to produce a material, from the extraction of raw materials to the manufacture of the finished product. Wood has a significantly lower embodied energy compared to steel, aluminium or concrete, making it the most sustainable construction material from an energy perspective.