internal walls and floors of buildings. The guidance relating to this part of the regulations is contained in
Section 5 of the Approved Document. In a typical domestic situation stud walls around bedrooms and
bathrooms need 75mm studwork with either two layers of plasterboard on each side, and 25mm of sound
insulation incorporated within the wall.
covered with floor boarding which achieves 15kg/m2 (i.e. 21mm tongued and grooved boarding) and this
should cover the entire floor and remaining ceiling joists to the eaves. This boarding should also be provided
with screw fixings. 100mm mineral wool insulation should be provided between the new floor joists, insulation
to be a minimum of 10kg/m2 (see diagram below).
minimum mass per unit area 10kg/
m2;
minimum distance between linings
of 75mm, or metal frame with a
minimum distance between linings
of 45mm;
mineral wool batts or quilt (minimum
thickness 25mm, minimum density
10kgg/m3) which may be wire
reinforced, suspended in the cavity;
of plasterboard, each sheet of
minimum mass per unit area 10kg/
m2;
minimum distance between linings of
75mm, or metal frame with a
minimum distance between linings of
45mm;
area 15kg/2;
area 10kg/m2, fixed using any normal fixing method; · an absorbant
layer of mineral wool (minimum thickness 100mm, minimum density
10kg/m3) laid in the cavity
should be made to improve their sound resistance.