To limit the spread of fire between fire compartments through external walls and the openings in them.
C4D4 Separation of external walls and associated openings in different fire compartments
Figure C4D4 illustrates the use of Table C4D4.
When the walls are at an angle of 180º or greater, the distance betweenthem may be zero because the effects of radiant heat between the walls is negligible. In practice, the distance between such walls is likely to equal the width of the fire wall.
Sole-occupancy units in Class 2 and Class 3 buildings are not fire compartments to which C4D4 applies.
C4D4 applies to both external walls. It does not apply to fire walls separating fire compartments. (A fire wall is not always an internal wall. See Figure C3D8c of this Guide).
Figure C4D4: Plan showing illustration of Table C4D4
Image
Image
