Section 6 Wall and ceiling linings

Wall and ceiling linings

  1. Classification of linings
    1. Definition of walls
      1. Definition of ceilings
      2. Variations and special provisions
        1. Walls
          1. Fire-protecting suspended ceilings
            1. Fire-resisting ceilings
              1. Rooflights
                1. Special applications
                2. Thermoplastic materials
                  1. General
                    1. Windows and internal glazing
                      1. Rooflights
                        1. Lighting diffusers
                        2. Suspended or stretched-skin ceilings

                          Classification of linings

                          Table 10

                          6.1Subject to the variations and specific provisions described in paragraphs 6.2 to 6.16, the surface linings of walls and ceilings should meet the following classifications:

                          Definition of walls

                          6.2For the purpose of the performance of wall linings, a wall includes:

                          • athe surface of glazing (except glazing in doors); and
                          • bany part of a ceiling which slopes at an angle of more than 70deg to the horizontal.

                          But a wall does not include:

                          • cdoors and door frames;
                          • dwindow frames and frames in which glazing is fitted;
                          • e architraves, cover moulds, picture rails, skirtings and similar narrow members; or
                          • ffireplace surrounds, mantle shelves and fitted furniture.

                          Definition of ceilings

                          6.3For the purposes of the performance of ceiling linings, a ceiling includes:

                          • athe surface of glazing;
                          • bany part of a wall which slopes at an angle of 70deg or less to the horizontal;
                          • cthe underside of a mezzanine or gallery; and
                          • dthe underside of a roof exposed to the room below.

                          But a ceiling does not include:

                          • etrap doors and their frames;
                          • fthe frames of windows or rooflights (see Appendix E) and frames in which glazing is fitted; or
                          • garchitraves, cover moulds, picture rails, exposed beams and similar narrow members.

                          Variations and special provisions

                          Walls

                          6.4Parts of walls in rooms may be of a poorer performance than specified in paragraph 6.1 and Table 10 (but not poorer than Class 3 (National class) or Class D-s3, d2 (European class)), provided the total area of those parts in any one room does not exceed one half of the floor area of the room; and subject to a maximum of 20m2 in residential accommodation and 60m2 in non- residential accommodation.

                          Fire-protecting suspended ceilings

                          6.5A suspended ceiling can contribute to the overall fire resistance of a floor/ceiling assembly. Such a ceiling should satisfy paragraph 6.1 and Table 10. It should also meet the provisions of Appendix A, Table A3.

                          Fire-resisting ceilings

                          6.6Cavity barriers are needed in some concealed floor or roof spaces (see Section 9); however, this need can be reduced by the use of a fire-resisting ceiling below the cavity. Such a ceiling should comply with Diagram 35.

                          Rooflights

                          6.7Rooflights should meet the relevant classification in 6.1 and Table 10. However plastic rooflights with at least a Class 3 rating may be used where 6.1 calls for a higher standard, provided the limitations in Table 11 and Table 18 are observed.

                          Notes:No guidance is currently possible on the performance requirements in the European fire tests as there is no generally accepted test and classification procedure.

                          Special applications

                          6.8Any flexible membrane covering a structure (other than an air supported structure) should comply with the recommendations given in Appendix A of BS 7157:1989.

                          6.9Guidance on the use of PTFE-based materials for tension-membrane roofs and structures is given in a BRE report Fire safety of PTFE-based materials used in buildings (BR 274, BRE 1994).

                          Thermoplastic materials

                          General

                          6.10Thermoplastic materials (see Appendix A, paragraph 17) which cannot meet the performance given in Table 10, can nevertheless be used in windows, rooflights and lighting diffusers in suspended ceilings if they comply with the provisions described in paragraphs 6.11 to 6.15. Flexible thermoplastic material may be used in panels to form a suspended ceiling if it complies with the guidance in paragraph 6.16. The classifications used in paragraphs 6.11 to 6.16, Table 11 and Diagram 27 are explained in Appendix A, paragraph 20.

                          Notes:No guidance is currently possible on the performance requirements in the European fire tests as there is no generally accepted test and classification procedure.

                          Windows and internal glazing

                          6.11External windows to rooms (though not to circulation spaces) may be glazed with thermoplastic materials, if the material can be classified as a TP(a) rigid product. Internal glazing should meet the provisions in paragraph 6.1 and Table 10 above.

                          Notes:A “wall” does not include glazing in a door (see paragraph 6.2).
                          Attention is drawn to the guidance on the safety of glazing in Approved Document N Glazing – safety in relation to impact, opening and cleaning.

                          Rooflights

                          6.12Rooflights to rooms and circulation spaces (with the exception of protected stairways) may be constructed of a thermoplastic material if:

                          • athe lower surface has a TP(a) (rigid) or TP(b) classification;
                          • bthe size and disposition of the rooflights accords with the limits in Table 11 and with the guidance to B4 in Tables 17 and 18.

                          Lighting diffusers

                          Diagram 26

                          6.13The following provisions apply to lighting diffusers which form part of a ceiling and are not concerned with diffusers of light fittings which are attached to the soffit of, or suspended beneath, a ceiling (see Diagram 26). Lighting diffusers are translucent or open- structured elements that allow light to pass through. They may be part of a luminaire or used below rooflights or other sources of light.

                          6.14Thermoplastic lighting diffusers should not be used in fire-protecting or fire-resisting ceilings, unless they have been satisfactorily tested as part of the ceiling system that is to be used to provide the appropriate fire protection.

                          6.15Subject to the above paragraphs, ceilings to rooms and circulation spaces (but not protected stairways) may incorporate thermoplastic lighting diffusers if the following provisions are observed:

                          • aWall and ceiling surfaces exposed within the space above the suspended ceiling (other than the upper surfaces of the thermoplastic panels) should comply with the general provisions of paragraph 6.1 and Table 10, according to the type of space below the suspended ceiling.
                          • bIf the diffusers are of classification TP(a) (rigid), there are no restrictions on their extent.
                          • cIf the diffusers are of classification TP(b), they should be limited in extent as indicated in Table 11 and Diagram 27.

                          Suspended or stretched-skin ceilings

                          Table 11

                          6.16The ceiling of a room may be constructed either as a suspended or as a stretched skin membrane from panels of a thermoplastic material of the TP(a) flexible classification, provided that it is not part of a fire-resisting ceiling. Each panel should not exceed 5m2 in area and should be supported on all its sides.