Building Construction Handbook, Eighth Edition

Plasterboard lining to stud framed partition walls satisfies the
Building Regulations, Approved Document B † Fire safety, as a
material of ``limited combustibility'' with a Class O rating for
surface spread of flame (Class O is better than Classes 1 to 4 as
determined by BS 476-7). The plasterboard dry walling should
completely protect any combustible timber components such as
sole plates. The following shows typical fire resistances as applied
to a metal stud frame ~

30 minute fire resistance

75 mm

Height limit 2.500

self drilling/self tapping screw fixings

metal channel stud frame

12.5 mm wallboard

staggered screw fixings

2 Nƒ 12.5 (15) mm

wallboards

60(90) minute fire resistance

100 mm

(110)

Height limit 3.400 (3.700)

110 mm

120 minute fire resistance

Height limit

4.200 metal box stud frame

2 Nƒ 15 mm

firecheck

plasterboards

For plasterboard types see page 642.

Stud Partitions -- Fire Protection