Custom Precast Elements

What is a custom precast element?

A custom precast element is a concrete member designed around the architectural or technical needs of a particular project, with molds and reinforcement prepared specifically for it. This group covers parts that fall outside the standard product range but still benefit, in quality and speed, from being produced under plant conditions.

When is it needed?

• When the project calls for a size, shape or opening outside standard sections
• When an element needs a service penetration, a door or window opening, or a special connection detail
• When a part would be difficult, slow or risky in quality terms to cast in place on site
• When the same special part repeats many times across the project and series production pays off
• When a particular shape or texture is wanted on an exposed surface

Standard or custom?

Not every unusual requirement needs a special mold. In many cases, adding a corbel, an opening or cast-in parts to a standard column or beam is enough, and it is the more economical route. A custom mold makes sense when the geometry is genuinely different or when the same part repeats enough times across the project. Drawing this line at the start of the project has a direct effect on cost and schedule.

How does the process work?

1. Defining the need: the element's role, dimensions and loads are reviewed from the architectural and structural drawings.
2. Manufacturability review: mold making, reinforcement layout, weight, lifting points, transport and erection conditions are assessed together.
3. Design and approval: production drawings are prepared and agreed with the project's designer of record.
4. Molding and production: a project-specific mold is built, and the element is cast and cured in the plant.
5. Delivery and erection: the element is delivered in line with the erection plan and installed in position.

Key considerations

Weight and size are the deciding factors for custom elements. Each part must be transportable by road and safely liftable with the crane available on site, so large pieces can be designed as smaller segments to be joined on site where needed. Because mold costs are spread across the number of units produced, the quantity of identical elements has a direct effect on unit cost. Preparing a custom mold takes extra time, so production of these elements is scheduled together with the overall project program.

Connection details matter as much as they do for standard members. How a custom part connects to the column, beam or roof system should be designed from the outset in line with the earthquake code.

Whether a given custom element can be produced, and its technical values, are confirmed project by project after reviewing the drawings. Share your drawings or describe your requirement to request an assessment.