Technical Booklet E Fire Safety·Page 98·Table 4.2 Notes
Notes on fire resistance table - basement floors and compartment walls
The floor over a basement must meet the higher of either the basement or ground/upper storey provisions. Fire resistance periods are increased to 60 minutes for compartment walls separating buildings.
The floor over a basement (or if there is more than one basement, the floor over the topmost basement) should meet the provisions for the ground and upper storeys if that period is higher.
* Increased to a minimum of 60 minutes for compartment walls separating buildings.
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