Concealed Work

in construction, a name for the work that cannot be inspected at the time the building or structure is completed. Concealed work includes work connected with structural foundations, for example, lowering the level of ground water, strengthening foundation soils, and sinking caissons. Earthwork, another type of concealed work, is concerned with the creation of embankments, foundations, trenches, ditches, earth dams, and levees and with the covering and insulating of foundations.

Reinforced concrete is also used in concealed work. This type of work includes the reinforcement of structures built with concrete slabs, the installation, protection against corrosion, and welding of placing components, and the unifying of the butt joints of individual reinforced-concrete structural components.

In the construction of metal and wood structures, concealed work includes the covering up of metal beams, girders, and columns, the implementation of measures to prevent corrosion, the application of agents to the wood to prevent rot and combustion, and the installation and fastening of door and window units. In the construction of floors and roofs, concealed work includes the work done on the sub-structures and lower layers.

In accordance with current construction standards and rules in the USSR, concealed work must be inspected by the proper construction organization before being concealed by subsequent work. When the building is completed, documentation pertaining to concealed work is included in the general acceptance report. High quality in concealed work improves the reliability of buildings and structures.