Commercial Construction Methods
The structural framework of large buildings such as office buildings, hospitals, apartment houses, and hotels is usually made from concrete or structural steel. The exterior finish is often concrete panels that are either prefabricated and raised into place, or poured into forms built at the site.
Floors are usually made of concrete that is poured at the site using wood, metal, or fiberglass forms.
Exterior walls (curtain walls) may also be made of glass in a metal or concrete framework. Before the concrete is poured, provision must be made for electrical, plumbing, and data cabling pathways. In some buildings, the framework is made of structural steel and the floors of poured concrete. Panels fabricated off site are lifted into place and bolted or welded to the steel.
In some specialized commercial applications, tilt-up concrete construction is used. In tilt-up construction, the wall panels are usually poured on the concrete floor slab, which are then tilted into place on the footing using a crane. The panels are welded together.
The main difference between tilt-up and other types of large commercial construction is that there is no steel or concrete framework in tilt-up construction. The walls and floor slab bear the entire load.
Tilt-up is most common in one- or two-storey buildings with a slab at grade (no below-grade foundation). It is popular for warehouses, low-rise offices, churches, and a variety of other commercial and multi-family residential applications.
Tilt-up panels of 50 feet in height are not uncommon.