Film-faced plywood is a type of plywood sheet that has been coated on both faces with a thin layer of phenolic resin film, creating a smooth, water-resistant surface ideal for use as concrete formwork. The film prevents the concrete from bonding to the board, makes stripping easier, and allows the panels to be reused multiple times.
The plywood core is typically made from birch, poplar, or a combination of hardwood veneers, laminated with waterproof adhesive. Standard sheet sizes are 2440 x 1220 mm or 2500 x 1250 mm, with thicknesses ranging from 12 mm to 21 mm. The most common thickness for formwork is 18 mm, which provides a good balance of stiffness and weight.
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Application
Film-faced plywood is the go-to material for building formwork — the temporary mould into which fresh concrete is poured. It is used for walls, columns, beams, slabs, and foundations. The smooth film surface produces a clean, fair-faced concrete finish, which is important when the concrete will remain exposed in the finished building.
For DIY builders, film-faced plywood is practical for casting foundation walls, garden walls, concrete countertops, or any project where a smooth concrete surface matters. Compared to regular construction plywood, the film coating significantly extends the lifespan of the board. A well-maintained sheet can be used for 20 to 50 pours, depending on the concrete type and how carefully the boards are handled and stored.
To get the most reuse out of your panels, apply a release agent (form oil) before each pour, clean the surface after stripping, and store the sheets flat and dry. Avoid dragging concrete-encrusted boards across rough surfaces, as this damages the film.
The edges of film-faced plywood are typically sealed with paint to prevent moisture ingress, but resealing cut edges with edge paint or wax is recommended after cutting panels to size.
Related terms
- Formwork
- Plywood
- Concrete
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