In relation to a building wall panel, a precast panel is a concrete slab which is cast in a factory or casting facility, transported to site and then placed into its final position by crane.
Precast can also refer to other precast or made concrete elements, such as; sock wells, retaining panels or other concrete goods which may be used on a construction project.
The term Precast Construction is distinct from, and often confused with tilt up construction although it is regularly used interchangeably.
The key difference being that precast panels are manufactured off site, and then transported to site and placed into their final position.
Precast panels are a precision product and exhibit a superior finish. They are suitable for projects where an exceptionally high standard of finish to wall surfaces is required.
Due to a relatively higher cost, in Western Australia, precast panels are generally not specified for your typical tilt panel projects. This may include; factory units developments, warehouses and other industrial projects.
However we have had them specified and used precast panels in the past for such projects and ther commercial projects, such as; offices, showrooms, shops, schools, etc.
Precast or off site cast panels may be necessary in certain circumstances.
Where these is:
– insufficent room or access onsite for casting panels and placing them into position by
– exceptionally high finish is required; or
– where casting of panels is unable to be achieved onsite due to space or construction
Precast also lends itself to smaller panels, or more irregular sizes and shapes than tilt up construction allows.
Coloured conrete and cast in textures can be used to enhance the outward appearance, although this will all add costs to a project.
The cost for a precast building panel may differ between projects.
In our experience a precast wall panel that is equivalent to a tilt up panel (albeit slammer so it can be transported) can range from $160 – $250 per m2 (once transport cost have been considered).
This cost will depend on the number of panels with; a common size and individual panel thickness, shape, weight (for transportation and lifting) and application.
Where insufficent floor space is provided for casting, or where a high quality post construction slab is required; the provision of temporary casting beds and the removal or disposal can add significant costs to concrete wall panels on a project.
This can offset the cost of using precast panels on a project.
One of the key benefits of the precast panels is that they can be manufactured off site ahead of time. This avoids the need for several weeks of on site casting.
They can also be erected without a floor slab, allowing for superior quality post construction slab in lieu of a delay pour slab to be poured late in the project. For little or no additional cost, in addition to, the additional upfront cost of using precast panels.
Precast wall panels have an inherent fire rating characteristic similar to tilt up panels, due to the concrete used during manufacture. They can also be placed on the boundary or as full height walls to provide a fire rating to the building or different areas within it.
As a second-generation family business, Mapel Building has been designing and constructing commercial and industrial buildings in Perth, Western Australia for over 25 years.