Fire rated partitions are internal walls that provide vertical fire separation, for example in dividing walls. In the main, these will be non-load bearing. A fire rated partition is a partition for which the fire resistance performance has been determined according to the appropriate European standards. Similarly, the reaction to fire performance of the exposed surfaces is also determined by the appropriate fire test standards. The requirement to determine the fire resistance and the reaction to fire performance of a partition is stated in current building regulations.

Partitions may be constructed in a variety of ways and the designer's specification will depend on the intended use, performance levels and the standards of finish and appearance required. Partitions may be formed from various types of sheet materials, supported by and concealing timber or metal stud framework, with or without expressed/ featured joints. They may also be constructed by using composite panels supported by an exposed framework, or prefabricated panels, butted together in floor and head tracks, with or without a supporting frame.

Once a fire has become fully developed it will attack the structure of the compartment and try to spread beyond the compartment of origin. A fire rated (fire resisting) partition prevents this by providing a construction, which will not collapse and will contain ('compartment') the fire for a given period of time. It is necessary to determine the fire resistance of the partition by assessing the behavior when subjected to defined heating and pressure conditions, which may be encountered in a fully developed fire.

Fire resistance tests employ a standard temperature/time curve, and pressure distribution for this purpose. The fire resistance of such partitions ranges from 30 to 240 minutes (or more). Paroc has an ETA for EI 45, EI 60 and EI90 partitions.

If an element that is intended to provide fire separation (i.e. it has requirements for fire resistance in terms of integrity and insulation) is to be effective, then every joint, or imperfection of fit, or opening to allow services to pass through the element, should be adequately protected by sealing or fire-stopping so that the fire resistance of the element is not impaired.