Section 6: Rooms for residential purposes

Introduction

6.1 Rooms for residential purposes are defined in Regulation 2 of the Building Regulations 2010. This definition is reproduced after the Requirements in this Approved Document.

6.2 This Section gives examples of wall and floor types, which, if built correctly, should meet the performance standards set out in Section 0: Performance - Table 1b.

6.3 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 1b. Advice should be sought from the manufacturer or other appropriate source.

Separating walls in new buildings containing rooms for residential purposes

6.4 Of the separating walls described in Section 2 the following types are most suitable for use in new buildings containing rooms for residential purposes:

Wall type 1. Solid masonry

• Wall type 1.1, Dense aggregate concrete block, plaster on both room faces;

• Wall type 1.2, Dense aggregate concrete in situ, plaster on both room faces;

• Wall type 1.3, Brick, plaster on both room faces.

Note: Plasterboard may be used as an alternative wall finish, provided a sheet of minimum mass per unit area 10kg/m² is used on each room face.

Wall type 3. Masonry between independent panels

• Wall type 3.1, Solid masonry core (dense aggregate concrete block), independent panels on both room faces.

• Wall type 3.2, Solid masonry core (lightweight concrete block), independent panels on both room faces.

Note: Wall types 2 and 4 can be used provided that care is taken to maintain isolation between the leaves. Specialist advice may be needed.

Corridor walls and doors

6.5 Separating walls described in 6.4 should be used between rooms for residential purposes and corridors in order to control flanking transmission and to provide the required sound insulation between the dwelling and the corridor. However, it is likely that the sound insulation will be reduced by the presence of a door.

6.6 Ensure any door has good perimeter sealing (including the threshold where practical) and a minimum mass per unit area of 25kg/m².
Alternatively, use a doorset with a minimum sound reduction index of 29dB Rw (measured in the laboratory according to BS EN ISO 140-3:1995 and rated according to BS EN ISO 717-1:1997). The door should also satisfy the Requirements of Building Regulation Part B – Fire safety.

6.7 Noisy parts of the building (e.g. function rooms or bars) should preferably have a lobby, double door or high performance doorset to contain the noise. Where this is not possible, nearby rooms for residential purposes should have similar protection. However, do ensure that there are doors that are suitable fordisabled access, see Building Regulations Part M - Access and facilities for disabled people.

Separating floors in new buildings containing rooms for residential purposes

6.8 Of the separating floors described in Section 3 the following types are most suitable for use in new buildings containing rooms for residential purposes:

Floor type 1. Concrete base with soft covering

• Floor type 1.1C Solid concrete slab (cast in situ, with or without permanent shuttering), soft floor covering, ceiling treatment C.

• Floor type 1.2B Concrete planks (solid or hollow), soft floor covering, ceiling treatment B.

Note Floor types 2 and 3 can be used provided that floating floors and ceilings are not continuous between rooms for residential purposes. Specialist advice may be needed.

Rooms for residential purposes resulting from a material change of use

6.9 It may be that an existing wall, floor or stair in a building that is to undergo a material change of use will achieve the performance standards set out in Section 0: Performance - Table 1b without the need for remedial work. This would be the case if the construction was similar (including flanking constructions) to one of the constructions in paragraphs 6.4 and 6.8 (e.g. for solid walls and floors the mass requirement should be within 15% of the mass per unit area of a construction listed in the relevant section).

6.10 For situations where it cannot be shown that the existing construction will achieve the performance standards set out in Section 0: Performance - Table 1b, Section 4 describes wall, floor and stair treatments to improve the level of sound insulation in dwellings formed by material change of use. These treatments may be used in buildings containing rooms for residential purposes. Specialist advice may be needed.

Junction details

6.11 In order for the construction to be fully effective, care should be taken to detail correctly the junctions between the separating wall and other elements, such as floors, roofs, external walls and internal walls.

6.12 In the case of new buildings containing rooms for residential purposes, refer to the guidance in Sections 2 and 3 which describes the junction and flanking details for each of the new build separating wall and floor types.

6.13 When rooms for residential purposes are formed by material change of use, refer to the notes and diagrams in Section 4 that describe the junction and flanking details for the wall and floor treatments.

6.14 In the case of the junction between a solid masonry separating wall type 1 and the ceiling void and roof space, the solid wall need not be continuous to the underside of the structural floor or roof provided that:

a. there is a ceiling consisting of two or more layers of plasterboard, of minimum total mass per unit area 20kg/m²;

b. there is a layer of mineral wool (minimum thickness 200mm, minimum density 10kg/m³) in the roof void;

c. the ceiling is not perforated.

The ceiling joists and plasterboard sheets should not be continuous between rooms for residential purposes. See Diagram 6.1.

6.15 This ceiling void and roof space detail can only be used where the Requirements of Building Regulations Part B - Fire safety can also be satisfied. The Requirements of Building Regulations Part L - Conservation of fuel and power should also be satisfied.

Diagram 6.1 Ceiling void and roof space

Room layout and building services design considerations

6.16 Internal noise levels are affected by room layout, building services and sound insulation.

6.17 The layout of rooms should be considered at the design stage to avoid placing noise sensitive rooms next to rooms in which noise is generated.

6.18 Additional guidance is provided in BS 8233:1999 Sound insulation and noise reduction for buildings. Code of practice and sound control for homes. See Annex D: References.