Fire partitioning walls are typically constructed of plaster board partitions. Fire-rated partitions are internal walls that provide vertical fire separation in structures such as dividing walls. These walls are typically 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 attacks the structure of the compartment and tries to spread beyond the compartment of origin. A fire-rated (fire-resisting) partition prevents this by creating a structure (i.e., a compartment) which does not collapse and contains the fire for a given period of time. It is necessary to determine the fire resistance of the partition by assessing the behaviour 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 EI 90 partitions. 

Timber structures

Fire is one of the first issues raised when timber frame construction is discussed. However, timber frame buildings must meet the same fire regulations as all other types of construction and therefore pose no greater risk to their inhabitants.

Timber stud partitions and timber joist floors have been used for many years as fire separating elements and their performance has been proven time and time again in test and real fire situations. Timber has a high and predictable performance in fire because timber chars at a slow and known rate of ~ 40 mm per hour. More importantly, it retains its structural integrity.

If the fire classification of the construction has to be increased it can be done by using PAROC stone wool in timber structures.

For example:
According to the addition method, a partition wall with 95mm timber studs and 12mm chip board on both sides, gives the following fire performance:

Partition wall without insulation
  1. Without insulation (air gap) = 24.0 minutes
  2. With 95mm glass wool insulation = 29.7 minutes
  3. With 95mm stone wool insulation = 69.0 minutes
Read more about addition method (pdf) >>