Because precast concrete can be cast at ground level in factory conditions, it has these added features:
Better finishes can be obtained with precast concrete because the inside surface of the mould is kept in good condition.
There is no grout loss, such as that from badly fitting formwork, which results in poor quality concrete like shown below.
By careful selection of materials and finishing processes, a wide range of high quality finishes can be obtained.
No space needed on site for storing moulds and reinforcement:
Precast components are made in a factory and delivered to site where they are lifted straight from the lorry onto the building.
Faster erection at site:
Components are erected straight from the delivery lorry. This leads to faster erection , where the difference between in-situ and precast construction is as shown below:
In both cases there is considerable amount of finishing work to be carried out. This is often less in precast than in-situ work due to the quality of the products.