Concrete formwork is a temporary or permanent mould into which fresh concrete is poured to shape it until it has cured sufficiently to support itself. The choice of formwork type depends on the shape of the structural element, the number of reuses required, the desired surface finish, and the available budget. Below is an overview of the most common formwork types used in construction.
Applications
Traditional timber formwork
The oldest and most versatile form of formwork. It is assembled on site from sawn timber, plywood sheets, and supporting props. Suitable for unique shapes and smaller projects, though it is labour-intensive and offers limited reuse.
- Film-faced plywood or birch plywood sheathing panels
- Planed boards for exposed concrete (fair-faced) finishes
- Timber props and ledger beams for support
System formwork
Standardised, modular formwork systems manufactured by companies such as Doka, PERI, and Hunnebeck. The panels consist of steel or aluminium frames with a forming face and are connected using quick-release clamps and ties.
- Wall formwork — large panels for casting straight walls
- Slab formwork (table formwork) — support systems for casting concrete floor slabs
- Fast assembly and striking, high reuse rates, consistent concrete quality
Climbing formwork
Specifically designed for tall structures such as high-rise buildings, towers, and silos. The formwork advances upward section by section as each concrete pour reaches sufficient strength.
- Crane-climbed formwork — lifted to the next level by crane after each pour
- Self-climbing formwork — climbs hydraulically along the previously cast wall
Slip formwork (slipforming)
A continuous process in which the formwork slowly slides upward while concrete is placed and cures. Ideal for uniform, tall structures.
- Silos, chimneys, bridge piers, and lift shafts
- Operates around the clock in shifts
Tunnel formwork
A U-shaped mould that allows walls and floor slab to be cast in a single operation. Widely used in repetitive residential construction.
- Short cycle times through repetitive casting sequences
- Smooth surfaces requiring minimal finishing
Circular formwork
Specialist formwork for curved or cylindrical shapes such as round columns, water towers, or architectural staircases. Available in steel, plastic, or flexible plywood configurations.
Related terms
- Formwork face (sheathing)
- Striking time
- Cast-in-place concrete
- Reinforcement steel
- Form ties
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