Structural class is a kind of a classification of structures.
Classification of the structures according to the Eurocode is done based on the expected design life.
Further, classification is also based on the type of structure or in other words, it could be interpreted as the importance of the structure. Very important structures such as monumental buildings, bridges, etc. are designed to last longer than the other structures.
The structural class is mention in the standard, Basics of the Structural Design (EC0).
Classification is solely based on the durability of the structure. It specifies the design life for the structures depending on its type and design life.
The following table indicates the classification of the structures depending on the type and durability.
| Design Working Life Category | Design Working Life | Example Structure |
| 1 | < 10 | Temporary structures |
| 2 | 10 to 25 | Replaceable structural parts; gantry girders, bearings |
| 3 | 15-30 | Agricultural and similar structures |
| 4 | 50 | Building structures and other similar structures |
| 5 | 100 | Monumental buildings, bridges, and other civil engineering structures |
| 6 | > 100 | Special structures |
After selecting the structural class, durability requirements can be finalized.
For example, structure to be built close to the sea, it is required to select the cover to the reinforcements.
When the structural class is know based on the type of the structures from the above table, cover to the reinforcement can be obtained depending on the exposure class specified in Eurocode 2.
