Concrete Countertops Cast on Site or in the Shop
There are two ways to build concrete countertops. Countertops are either precast, where they are built in a shop, or they are built in place at the job site.
Countertops that are precast are poured in the contractor's shop. Many contractors prefer this method because they can control the environment that the countertops are in. There is less risk to the countertop when it is precast. The contractor has control over the temperature as the concrete cures. The countertop is also in a protected area at the contractor's shop where it has less risk of being damaged by other trades, etc. One condition to deciding if countertops should be precast is that they then must be shipped or moved and installed. Sometimes, the size of the countertop is not feasible for lifting and placing by hand.
Cast-in-place countertops are built on site. This method is preferred when there are unique edges, forms, curves or other significant challenges to the construction of the countertop. Also, if the countertop has long runs or is going to be extremely heavy, a contractor may decide to cast-in-place. The downside to countertops built on site is that the process can be extremely messy which is sometimes not acceptable to homeowners or business owners.