2.1 This Section gives examples of wall types which, if built correctly, should achieve the performance standards set out in Section 0: Performance - Table 1a.
2.2 The guidance in this section is not exhaustive and other designs, materials or products may be used to achieve the performance standards set out in Section 0: Performance - Table 1a. Advice should be sought from the manufacturer or other appropriate source.
2.3 The walls are grouped into four main types. See Diagram 2-1.
2.4 Wall type 1: Solid masonry The resistance to airborne sound depends mainly on the mass per unit area of the wall.
2.5 Wall type 2: Cavity masonry The resistance to airborne sound depends on the mass per unit area of the leaves and on the degree of isolation achieved. The isolation is affected by connections (such as wall ties and foundations) between the wall leaves and by the cavity width.
2.6 Wall type 3: Masonry between independent panels The resistance to airborne sound depends partly on the type and mass per unit area of the core, and partly on the isolation and mass per unit area of the independent panels.
2.7 Wall type 4: Framed walls with absorbent material The resistance to airborne sound depends on the mass per unit area of the leaves, the isolation of the frames, and the absorption in the cavity between the frames.
2.8 Within each wall type the constructions are ranked, as far as possible, with constructions providing higher sound insulation given first.
2.9 In order for the construction to be fully effective, care should be taken to correctly detail the junctions between the separating wall and other elements, such as floors, roofs, external walls and internal walls. Recommendations are also given for the construction of these elements, where it is necessary to control flanking transmission. Notes and diagrams explain the junction details for each of the separating wall types.
Diagram 2-1: Types of separating wall
Resistance to the passage of sound 16