Technical Booklet E Fire Safety·Page 102·4.12
Basement storey open at ground level
Where a basement storey or compartment is open at ground level on one side and provides means of escape, fire and rescue access, and smoke venting, the fire resistance period required should be that appropriate to a storey above ground.
Where one side of a basement storey or compartment is (due to the slope of the ground) open at and provides – means of escape and fire and rescue access at ground level and smoke venting, the period of resistance for the elements of structure and other components of the building in that basement storey or compartment should be that appropriate to a storey above the ground.
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