What is film faced plywood used for?

Concrete formwork, almost exclusively. The resin-impregnated film gives a smooth release surface so the concrete comes out fair-faced, and it protects the board so it can be stripped and re-used. It is also used for transport flooring and hoarding, but formwork is the main application.

What film weight should I specify?

Match it to the number of pours you need. 120 g/m2 gives roughly 3 to 5 cycles, 240 g/m2 about 6 to 10, and 320 g/m2 ten or more. Film weight alone does not decide life: glue type, core species and edge sealing matter as much or more.

Why do my formwork panels delaminate after a few pours?

Most often unsealed edges. Water enters at the cut edge, the plies swell and lift, and the film separates from the inside out. Seal every cut edge with two coats of water-resistant paint before first use. The second most common cause is MR glue instead of WBP on wet pours.

Is film faced plywood the same as marine plywood?

No. Film faced plywood has a resin film on the faces and is built for concrete formwork. Marine plywood to BS 1088 has no film, uses hardwood veneers with no core gaps, and is built for boat building and permanent wet service. They are not interchangeable.

Can I get film faced plywood in other thicknesses?

Yes. 18 mm is the most common for formwork, with 12, 15 and 21 mm also produced. Thickness affects stiffness and how the panel behaves under pour pressure, so it should follow from the formwork design rather than from what happens to be in stock.

Film Faced Plywood 18mm: Film Weight, Glue and Re-use

What You Are Actually Buying

Film faced plywood is a plywood core with a resin-impregnated paper bonded to both faces under heat and pressure. It exists for one job: to be the surface that concrete cures against, and then to be stripped off and used again.

Three things decide how many times it survives that cycle, and only one of them is the one buyers usually ask about.

Film Weight, Glue and Core

Variable	Common options	Effect
Film weight	120, 180, 240, 320 g/m² per face	The wear surface. Heavier film survives more stripping cycles and gives a smoother release.
Glue	WBP phenolic; MR (melamine urea) on cheaper boards	Decides whether the board delaminates when the concrete is still wet. WBP is the specification for formwork.
Core species	Poplar, eucalyptus, birch, pine, mixed hardwood	Decides stiffness, weight and how the board behaves when re-used. Poplar is light and cheap; birch and eucalyptus are denser and hold the screw better.
Edge treatment	Unsealed, or sealed with water-resistant paint	The single most common cause of early failure. Water enters at the edge and the plies lift.

Film weight is the number most often quoted and the least decisive on its own. A 240 g board on a poplar core with unsealed edges will fail before a 180 g board on a eucalyptus core with sealed edges. Ask for all four.

How Many Re-uses to Expect

Film weight per face	Typical re-use, normal site conditions
120 g/m²	3–5 cycles
180 g/m²	5–8 cycles
240 g/m²	6–10 cycles
320 g/m²	10 or more cycles

These are the ranges the industry works to, not a guarantee. Actual life depends on how the boards are stripped, cleaned, stacked and stored between pours — and on the edge sealing, which the table does not capture. A formwork panel stored flat and dry will outlast one left in the sun.

Why Formwork Panels Fail Early

In order of how often we see it:

Unsealed edges. Water wicks in at the cut edge, the plies swell and lift, and the face film delaminates from the inside. Sealing the edges with two coats of water-resistant paint before first use roughly doubles service life for almost no cost.
Release agent applied too late, or not at all. Concrete bonds to the film and the surface tears on stripping.
Prying instead of lifting. A crowbar between the board and the concrete takes the film off in patches.
Stacked wet. Boards stacked face-to-face while damp trap moisture between the films.
Wrong glue for the pour. MR-glued boards used on wet pours delaminate from the core outward.

Surface Finish Options

Finish	Use
Glossy / smooth film	The default for fair-faced concrete. Gives the smoothest release and the best surface.
Anti-slip / mesh pattern	Slip resistance on the board itself — used for access decks and ramps rather than for concrete finish.
Printed or branded film	Mill identification. Cosmetic only.

For architectural concrete where the formwork pattern is part of the design, the film texture becomes a specification item in its own right and should be agreed against a sample panel before the order is placed.

How to Write the Order

Weak	Workable
"18 mm film faced plywood"	"18 mm, 1220 × 2440 mm, 240 g/m² film both faces, WBP phenolic glue, eucalyptus core, edges sealed"
"Shuttering plywood, cheap"	State the number of pours you need. The film weight follows from that, not from the price.
"Waterproof plywood"	Not a specification. Say WBP and name the standard you need it to meet.

If the panels are going to be cut on site, order edge sealant with them. It is the cheapest line on the order and the one that decides how many pours you get.