{{unreferenced, date=March 2010 In

civil engineering Civil engineering is a professional engineering discipline that deals with the design, construction, and maintenance of the physical and naturally built environment, including public works such as roads, bridges, canals, dams, airports, sewage ...

and

structural engineering Structural engineering is a sub-discipline of civil engineering in which structural engineers are trained to design the 'bones and muscles' that create the form and shape of man-made structures. Structural engineers also must understand and cal ...

, serviceability refers to the conditions under which a building is still considered useful. Should these

limit states Limit State Design (LSD), also known as Load And Resistance Factor Design (LRFD), refers to a design method used in structural engineering. A limit state is a condition of a structure beyond which it no longer fulfills the relevant design criteria ...

be exceeded, a structure that may still be structurally sound would nevertheless be considered unfit. It refers to conditions other than the building strength that render the buildings unusable. Serviceability limit state design of structures includes factors such as durability, overall stability, fire resistance, deflection, cracking and excessive vibration. For example, a

skyscraper A skyscraper is a tall continuously habitable building having multiple floors. Modern sources currently define skyscrapers as being at least or in height, though there is no universally accepted definition. Skyscrapers are very tall high-ris ...

could sway severely and cause the occupants to be sick (much like

sea-sickness Motion sickness occurs due to a difference between actual and expected motion. Symptoms commonly include nausea, vomiting, cold sweat, headache, dizziness, tiredness, loss of appetite, and increased salivation. Complications may rarely include d ...

), yet be perfectly sound structurally. This building is in no danger of collapsing, yet since it is obviously no longer fit for human occupation, it is considered to have exceeded its

serviceability limit {{unreferenced, date=March 2010 In civil engineering and structural engineering, serviceability refers to the conditions under which a building is still considered useful. Should these limit states be exceeded, a structure that may still be struc ...

state.

Serviceability limit

A serviceability limit defines the performance criterion for serviceability and corresponds to a conditions beyond which specified service requirements resulting from the planned use are no longer met. In

limit state design Limit State Design (LSD), also known as Load And Resistance Factor Design (LRFD), refers to a design method used in structural engineering. A limit state is a condition of a structure beyond which it no longer fulfills the relevant design criteria ...

, a structure fails its serviceability if the criteria of the serviceability limit state are not met during the specified service life and with the required reliability. Hence, the serviceability limit state identifies a civil engineering structure which fails to meet technical requirements for use even though it may be strong enough to remain standing. A structure that fails serviceability has exceeded a defined limit for one of the following properties: * Excessive

deflection Deflection or deflexion may refer to: Board games * Deflection (chess), a tactic that forces an opposing chess piece to leave a square * Khet (game), formerly ''Deflexion'', an Egyptian-themed chess-like game using lasers Mechanics * Deflection ...

* Vibration * Local deformation (engineering) Serviceability limits are not always defined by building code developer, government or regulatory agency. Building codes tend to be restricted to ultimate limits related to public and occupant safety. Global geopolitical variations are likely to exist. Structural engineering Building engineering