Rigid construction
Firestopping of service penetrations, Best practice in design and installation, was published in 2020. It is a collaboration between ASFP (Association for Specialist Fire Protection), FIS (Finishes and Interiors Sector), GPDA (Gypsum Products Development Association), BESA (Building Engineering Services Association) and BSRIA (Building Services Research and Information Association).
It defines rigid construction as a: ‘High density constructing element designed from block work, masonry or concrete with an overall density ≥850kg/m3 with a thickness appropriate for the expected fire resistance period or a low density constructing element made from aerated concrete block, masonry or lintels with an overall density of 650±200kg/m3 with a thickness appropriate for the expected fire resistance period.’
See also: Flexible construction.
--BSRIA
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