Appendix A Performance of materials, products and structures

Performance of materials, products and structures

  1. Introduction
    1. Fire resistance
      1. Roofs
        1. Reaction to fire
          1. Non-combustible materials
            1. Materials of limited combustibility
              1. Internal linings
                1. Thermoplastic Materials
                  1. Fire test methods

                    Introduction

                    1. Much of the guidance in this document is given in terms of performance in relation to British or European Standards for products or methods of test or design or in terms of European Technical Approvals. In such cases the material, product or structure should:
                    • A. be in accordance with a specification or design which has been shown by test to be capable of meeting that performance; or
                    Note: For this purpose, laboratories accredited by the United Kingdom Accreditation Service (UKAS) for conducting the relevant tests would be expected to have the necessary expertise.
                    • B. have been assessed from test evidence against appropriate standards, or by using relevant design guides, as meeting that performance; or
                    Note: For this purpose, laboratories accredited by UKAS for conducting the relevant tests and suitably qualified fire safety engineers might be expected to have the necessary expertise. For materials/products where European standards or approvals are not yet available and for a transition period after they become available, British standards may continue to be used. Any body notified to the UK Government by the Government of another Member State of the European Union as capable of assessing such materials/products against the relevant British Standards, may also be expected to have the necessary expertise. Where European materials/ products standards or approvals are available, any body notified to the European Commission as competent to assess such materials or products against the relevant European standards or technical approval can be considered to have the appropriate expertise.
                    • C. where tables of notional performance are included in this document, conform with an appropriate specification given in these tables; or
                    • D. in the case of fire-resisting elements:
                      • i: conform with an appropriate specification given in Part II of the Building Research Establishments’ Report Guidelines for the construction of fire-resisting structural elements (BR 128, BRE 1988); or
                      • ii: be designed in accordance with a relevant British Standard or Eurocode
                      Note: Different forms of construction can present different problems and opportunities for the provision of structural fire protection. Further information on some specific forms of construction can be found in:  
                    • Timber - BRE 454 Multi-storey timber frame buildings - a design guide 2003 ISBN: 1 86081 605 3
                    • Steel - SCI P197 Designing for structural fire safety: A handbook for architects and engineers 1999 ISBN: 1 85942 074 5
                      Note: Any test evidence used to substantiate the fire resistance rating of a construction should be carefully checked to ensure that it demonstrates compliance that is adequate and applicable to the intended use. Small differences in detail (such as fixing method, joints, dimensions and the introduction of insulation materials etc.) may significantly affect the rating. 2. Building Regulations deal with fire safety in buildings as a whole. Thus they are aimed at limiting fire hazard. The aim of standard fire tests is to measure or assess the response of a material, product, structure or system to one or more aspects of fire behaviour. Standard fire tests cannot normally measure fire hazard. They form only one of a number of factors that need to be taken into account. Other factors are set out in this publication.

                    Fire resistance

                    3. Factors having a bearing on fire resistance, that are considered in this document, are: A. fire severity; B. building height; and C. building occupancy. 4. The standards of fire resistance given are based on assumptions about the severity of fires and the consequences should an element fail. Fire severity is estimated in very broad terms from the use of the building (its purpose group), on the assumption that the building contents (which constitute the fire load) are similar for buildings in the same use. A number of factors affect the standard of fire resistance specified. These are: A. the amount of combustible material per unit of floor area in various types of building (the fire load density); B. the height of the top floor above ground, which affects the ease of escape and of firefighting operations, and the consequences should large scale collapse occur; C. occupancy type, which reflects the ease with which the building can be evacuated quickly; D. whether there are basements, because the lack of an external wall through which to vent heat and smoke may increase heat build-up and thus affect the duration of a fire, as well as complicating firefighting; and E. whether the building is of single storey construction (where escape is direct and structural failure is unlikely to precede evacuation). Because the use of buildings may change, a precise estimate of fire severity based on the fire load due to a particular use may be misleading. Therefore, if a fire engineering approach of this kind is adopted, the likelihood that the fire load may change in the future needs to be considered. 5. Performance in terms of the fire resistance to be met by elements of structure, doors and other forms of construction is determined by reference to either: A. (National tests) BS 476 Fire tests on building materials and structures, Parts 20-24:1987, i.e. Part 20 Method for determination of the fire resistance of elements of construction (general principles), Part 21 Methods for determination of the fire resistance of loadbearing elements of construction, Part 22 Methods for determination of the fire resistance of non-loadbearing elements of construction, Part 23 Methods for determination of the contribution of components to the fire resistance of a structure, and Part 24 Method for determination of the fire resistance of ventilation ducts (or to BS 476-8:1972 in respect of items tested or assessed prior to 1 January 1988); or B. (European tests) Commission Decision 2000/367/EC of 3 May 2000 implementing Council Directive 89/106/EEC as regards the classification of the resistance to fire performance of construction products, construction works and parts thereof. All products are classified in accordance with BBS EN 13501-2:2003 Fire classification of construction products and building elements. Classification using data from fire resistance tests, excluding ventilation services (excluding products for use in ventilation systems). BS EN 13501-3:2005 Fire classification of construction products and building elements. Classification using data from fire resistance tests on products and elements used in building service installations: fire resisting ducts and fire dampers (other than smoke control systems). BS EN 13501-4:2007, Fire classification of construction products and building elements, Part 4 - Classification using data from fire resistance tests on smoke control systems. The relevant European test methods under BS EN 1364, 1365, 1366 and 1634 are listed in Appendix F. Table A1 gives the specific requirements for each element in terms of one or more of the following performance criteria: A. resistance to collapse (loadbearing capacity), which applies to loadbearing elements only, denoted R in the European classification of the resistance to fire performance; B. resistance to fire penetration (integrity), denoted E in the European classification of the resistance to fire performance; and C. resistance to the transfer of excessive heat (insulation), denoted I in the European classification of the resistance to fire performance. Table A2 sets out the minimum periods of fire resistance for elements of structure. Table A3 sets out criteria appropriate to the suspended ceilings that can be accepted as contributing to the fire resistance of a floor. Table A4 sets out limitations on the use of uninsulated fire-resisting glazed elements. These limitations do not apply to the use of insulated fire-resisting glazed elements. Information on tested elements is frequently given in literature available from manufacturers and trade associations. Information on tests on fire-resisting elements is also given in such publications as:

                    Association for Specialist Fire Protection Yellow Book - Fire protection for structural steel in buildings, 4th edition. See Appendix F.

                    Roofs

                    6. Performance in terms of the resistance of roofs to external fire exposure is determined by reference to either:

                    • A. (National tests) BS 476-3:2004 External fire exposure roof tests; or
                    • B. (European tests) Commission Decision 2005/823/EC amending Decision 2001/671/ EC Establishing a classification system for the external fire performance of roofs and roof coverings
                    Constructions are classified within the National system by two letters in the range A-D, with an AA designation being the best. The first letter indicates the time to penetration; the second letter a measure of the spread of flame. Constructions are classified within the European system as BROOF(t4), CROOF(t4), DROOF(t4), EROOF(t4) or FROOF(t4) (with BROOF(t4) being the highest performance and FROOF(t4) being the lowest) in accordance with BS EN 13501-5:2005 Fire classification of construction products and building elements - Classification using data from external fire exposure to roof tests. BS EN 13501-5 refers to four separate tests. The suffix (t4) used above indicates that Test 4 is to be used for the purposes of this Approved Document. Some roof covering products (and/or materials) can be considered to fulfil all of the requirements for the performance characteristic "external fire performance" without the need for testing, subject to any national provisions on the design and execution of works being fulfilled. These roof covering products are listed in Commission Decision 2000/553/EC of 6th September 2000 implementing Council Directive 89/106/EEC as regards the external fire performance of roof coverings. In some circumstances roofs, or parts of roofs, may need to be fire-resisting, for example if used as an escape route or if the roof performs the function of a floor. Such circumstances are covered in Sections 2, 4 and 6. Table A5 gives notional designations of some generic roof coverings.

                    Reaction to fire

                    7. Performance in terms of reaction to fire to be met by construction products is determined by Commission Decision 200/147/EC of 8 February 2000 implementing Council Directive 89/106/EEC as regards the classification of the reaction to fire performance of construction products. Note: The designation of xxxx is used for the year reference for standards that are not yet published. The latest version of any standard may be used provided that it continues to address the relevant requirements of the Regulations. All products, excluding floorings, are classified as †A1, A2, B, C, D, E or F (with class A1 being the highest performance and F being the lowest) in accordance with BS EN 13501-1:2002 Fire classification of construction products and building elements, Part 1 - Classification using data from reaction to fire tests. The classes of reaction to fire performance of A2, B, C, D and E are accompanied by additional classifications related to the production of smoke (s1, s2, s3) and/or flaming droplets/particles (d0, d1, d2). The relevant European test methods are specified as follows:

                    • BS EN ISO 1182:2002 Reaction to fire tests for building products - Non-combustibility test
                    • BS EN ISO 1716:2002 Reaction to fire tests for building products - Determination of the gross calorific value
                    • BS EN 13823:2002 Reaction to fire tests for building products - Building products excluding floorings exposed to the thermal attack by a single burning item
                    • BS EN ISO 11925-2:2002 Reaction to fire tests for building products, Part 2 - Ignitability when subjected to direct impingement of a flame.
                    • BS EN 13238:2001 Reaction to fire tests for building products - conditioning procedures and general rules for selection of substrates.
                     

                    Non-combustible materials

                    8. Non-combustible materials are defined in Table A6 either as listed products, or in terms of performance:

                    • A.(National classes) when tested to BS 476-4:1970 Fire tests on building materials and structures - Non-combustibility test for materials or BS 476-11:1982 Fire tests on building materials and structures - Method for assessing the heat emission from building materials.
                    • B. (European classes) when classified as class A1 in accordance with BS EN 13501-1:2002 Fire classification of construction products and building elements. Classification using data from reaction to fire tests when tested to BS EN ISO 1182:2002 Reaction to fire tests for building products - Non-combustibility test and BS EN ISO 1716:2002 Reaction to fire tests for building products - Determination of the gross calorific value.
                      Table A6 identifies non-combustible products and materials, and lists circumstances where their use is necessary.

                    Materials of limited combustibility

                    9. Materials of limited combustibility are defined in Table A7:

                    • A. (National classes) by reference to the method specified in BS 476-11:1982;
                    • B. (European classes) in terms of performance when classified as class A2-s3, d2 in accordance with BS EN 13501-1:2002 Fire classification of construction products and building elements. Classification using data from reaction to fire tests when tested to BS EN ISO 1182:2002 Reaction to fire tests for building products - Non-combustibility test or BS EN ISO 1716:2002 Reaction to fire tests for building products - Determination of the gross calorific value and BS EN 13823:2002 Reaction to fire tests for building products - Building products excluding floorings exposed to the thermal attack by a single burning item.
                    Table A7 also includes composite products (such as plasterboard) which are considered acceptable, and where these are exposed as linings they should also meet any appropriate flame spread rating.

                    Internal linings

                    10. Flame spread over wall or ceiling surfaces is controlled by providing for the lining materials or products to meet given performance levels in tests appropriate to the materials or products involved. 11. Under the National classifications, lining systems which can be effectively tested for ‘surface spread of flame’ are rated for performance by reference to the method specified in BS 476- 7:1997 (or 1987 or 1971) Fire tests on building materials and structures. Method of test to determine the classification of the surface spread of flame of products under which materials or products are classified 1, 2, 3 or 4 with Class 1 being the highest. Under the European classifications, lining systems are classified in accordance with BS EN 13501-1:2002 Fire classification of construction products and building elements, Part 1 - Classification using data from reaction to fire tests. Materials or products are classified as A1, A2, B, C, D, E or F, with A1 being the highest. When a classification includes ‘s3, d2’, it means that there is no limit set for smoke production and/or flaming droplets/particles. 12. To restrict the use of materials which ignite easily, which have a high rate of heat release and/ or which reduce the time to flashover, maximum acceptable ‘fire propagation’ indices are specified, where the National test methods are being followed. These are determined by reference to the method specified in BS 476-6:1989 or 1981. Index of performance (I) relates to the overall test performance, whereas sub-index (i1) is derived from the first three minutes of test. 13. The highest National product performance classification for lining materials is Class 0. This is achieved if a material or the surface of a composite product is either:

                    • A. composed throughout of materials of limited combustibility; or
                    • B. a Class 1 material which has a fire propagation index (I) of not more than 12 and sub-index (i1) of not more than 6.
                      Note:Class 0 is not a classification identified in any British Standard test. 14. Composite products defined as materials of limited combustibility (see paragraph 9 and Table A7) should in addition comply with the test requirement appropriate to any surface rating specified in the guidance on requirements B2, B3 and B4. 15. The notional performance ratings of certain widely used generic materials or products are listed in Table A8 in terms of their performance in the traditional lining tests BS 476-6:1989 and BS 476-7:1997 or in accordance with BS EN 13501-1:2002. 16. Results of tests on proprietary materials are frequently given in literature available from manufacturers and trade associations. Any reference used to substantiate the surface spread of flame rating of a material or product should be carefully checked to ensure that it is suitable, adequate and applicable to the construction to be used. Small differences in detail, such as thickness, substrate, colour, form, fixings, adhesive etc, may significantly affect the rating.

                    Thermoplastic Materials

                    17. A thermoplastic material means any synthetic polymeric material which has a softening point below 200ºC if tested to BS EN ISO 306:2004 method A120 Plastics - Thermoplastic materials - Determination of Vicat softening temperature. Specimens for this test may be fabricated from the original polymer where the thickness of material of the end product is less than 2.5mm. 18. A thermoplastic material in isolation can not be assumed to protect a substrate when used as a lining to a wall or ceiling. The surface rating of both products must therefore meet the required classification. If, however, the thermoplastic material is fully bonded to a non- thermoplastic substrate, then only the surface rating of the composite will need to comply. 19. Concessions are made for thermoplastic materials used for window glazing, rooflights, and lighting diffusers within suspended ceilings, which may not comply with the criteria specified in paragraphs 11 to 16. They are described in the guidance on requirements B2 and B4. 20. For the purposes of the requirements B2 and B4 thermoplastic materials should either be used according to their classification 0-3, under the BS 476-6:1989 and BS 476-7:1997 tests as described in paragraphs 11 to 16, (if they have such a rating), or they may be classified TP(a) rigid, TP(a) flexible, or TP(b) according to the following methods:

                    TP(a) rigid:
                    i: Rigid solid pvc sheet; ii: Solid (as distinct from double- or multiple-skin) polycarbonate sheet at least 3mm thick; iii: Multi-skinned rigid sheet made from unplasticised pvc or polycarbonate which has a Class 1 rating when tested to BS 476-7:1997 or 1971 or 1987; and iv: Any other rigid thermoplastic product, a specimen of which (at the thickness of the product as put on the market), when tested to BS 2782:1970 as amended in 1974: Method 508A Rate of burning (Laboratory method), performs so that the test flame extinguishes before the first mark and the duration of flaming or afterglow does not exceed five seconds following removal of the burner.
                    TP(a) flexible:
                    Flexible products not more than 1mm thick which comply with the Type C requirements of BS 5867-2:1980 Specification for fabrics for curtains and drapes - Flammability requirements when tested to BS 5438:1989 Methods of test for flammability of textile fabrics when subjected to a small igniting flame applied to the face or bottom edge of vertically oriented specimens, Test 2, with the flame applied to the surface of the specimens for 5, 15, 20 and 30 seconds respectively, but excluding the cleansing procedure; and
                    TP(b):
                    i: Rigid solid polycarbonate sheet products less than 3mm thick, or multiple-skin polycarbonate sheet products which do not qualify as TP(a) by test; or ii: Other products which, when a specimen of the material between 1.5 and 3mm thick is tested in accordance with BS 2782:1970, as amended in 1974: Method 508A, has a rate of burning which does not exceed 50mm/minute. Table A1 - Specific provisions of test for fire resistance of elements of structure etc Table A1 - Specific provisions of test for fire resistance of elements of structure etc Table A1 continued Table A1 continued Note: If it is not possible to cut or machine a 3mm-thick specimen from the product then a 3mm test specimen can be moulded from the same material as that used for the manufacture of the product. Note:Currently, no new guidance is possible on the assessment or classification of thermoplastic materials under the European system since there is no generally accepted European test procedure and supporting comparative data.Notes:If it is not possible to cut or machine a 3mm-thick specimen from the product then a 3mm test specimen can be moulded from the same material as that used for the manufacture of the product.

                    Fire test methods

                    21. A guide to the various test methods in BS 476 and BS 2782 is given in PD 6520 Guide to fire test methods for building materials and elements of construction (available from the British Standards Institution). A guide to the development and presentation of fire tests and their use in hazard assessment is given in BS 6336:1998 Guide to development and presentation of fire tests and their use in hazard assessment.

                    Application of the fire resistance standards in table A2:
                    1. Where one element of structure supports or carries or gives stability to another, the fire resistance of the supporting element should be no less than the minimum period of fire resistance for the other element (whether that other element is loadbearing or not).
                    There are circumstances where it may be reasonable to vary this principle, for  example:
                    • where the supporting structure is in the open air, and is not likely to be affected by the fire in the building; or
                    • where the supporting structure is in a different compartment, with a fire-separating element (which has the higher standard of fire resistance) between the supporting and the separated structure; or
                    • where a plant room on the roof needs a higher fire resistance than the elements of structure supporting
                    2. Where an element of structure forms part of more than one building or compartment, that element should be constructed to the standard of the greater of the relevant
                    1. Although most elements of structure in a single storey building may not need fire resistance (see the guidance on requirement B3, paragraph 4.4(a)), fire resistance will be needed if the element:
                      1. is part of (or supports) an external wall and there is provision in the guidance on requirement B4 to limit the extent of openings and other unprotected areas in the wall; or
                      2. is part of (or supports) a compartment wall, including a wall common to two or more buildings, or a wall between  dwellinghouse and an attached or integral garage; or
                      3. supports a gallery
                    For the purposes of this paragraph, the ground storey of a building which has one or more basement storeys and no upper storeys, may be considered as a single-storey building. The fire resistance of the basement storeys should be that appropriate to  basements. Table A3 - Limitations on fire - protecting suspended ceilings (see Table A1, Note 4) Table A3 - Limitations on fire - protecting suspended ceilings (see Table A1, Note 4) Table A4 - Limitations on the use of uninsulated glazed elements on escape routes Table A4 - Limitations on the use of uninsulated glazed elements on escape routes (These limitations do not apply to glazed elements which satisfy the relevant insulation criterion, see Table A1) Table A5 - Notional designations of roof coverings Table A5 - Notional designations of roof coverings Table A6 - Use and definitions of non-combustible materials Table A6 - Use and definitions of non-combustible materials Table A7 - Use and definitions of materails of limited combustibillty Table A7 - Use and definitions of materials of limited combustibility Table A8 - Typical performance ratings of some generic materials and products Table A8 - Typical performance ratings of some generic materials and products

                    • Diagram1- Means of escape form dwellinghouses Diagram1 - Means of escape form dwellinghouses
                    • Diagram 2 - Alternative arrangements for final exits Diagram 2 - Alternative arrangements for final exits
                    • Diagram 3 - Fire separation in houses with more than one floor over 4.5m above ground level Diagram 3 - Fire separation in houses with more than one floor over 4.5m above ground level
                    • Diagram 4 - Ground or basement storey exit into an enclosed space Diagram 4 - Ground or basement storey exit into an enclosed space.
                    • Diagram 5 - Gallery floors with no alternative exit
                    • Diagram 6 - Alternative cavity barrier arrangements in roof space over protected stairway in a house with a floor more than 4.5m above ground level Diagram 6 - Alternative cavity barrier arrangements in roof space over protected stairway in a house with a floor more than 4.5m above ground level
                    • Diagram 7 - Fire resistance of areas adjacent to external stairs Diagram 7 - Fire resistance of areas adjacent to external stairs
                    • Diagram 8 - Lighting diffuser in relation to ceiling Diagram 8 - Lighting diffuser in relation to ceiling
                    • Diagram 9 - Layout restrictions on Class 3 plastice rooflights, TP(b) rooflights and TP(b) lighting diffusers Diagram 9 - Layout restrictions on Class 3 plastice rooflights, TP(b) rooflights and TP(b) lighting diffusers
                    • Diagram 10 - Separation between garage and dwellinghouse Diagram 10 - Separation between garage and dwellinghouse
                    • Diagram 11 - Junction of compartment wall with roof Diagram 11 - Junction of compartment wall with roof
                    • Diagram 12 - Interrupting concealed spaces (cavities) Diagram 12 - Interrupting concealed spaces (cavities)
                    • Diagram 13 - Cavity walls excluded from provisions for cavity barriers Diagram 13 - Cavity walls excluded from provisions for cavity barriers
                    • Diagram 14 - Pipes penetrating structure Diagram 14 - Pipes penetrating structure
                    • Diagram 15 - Enclosure for drainage or water supply pipes Diagram 15 - Enclosure for drainage or water supply pipes
                    • Diagram 16 - Fules penetrating compartment walls or floors Diagram 16 - Fules penetrating compartment walls or floors
                    • Diagram 17 - Relevant boundary Diagram 17 - Relevant boundary
                    • Diagram 18 - Notional boundary Diagram 18 - Notional boundary
                    • Diagram 19 - Status of combustible surface material as unprotected area Diagram 19 - Status of combustible surface material as unprotected area
                    • Diagram 20 - Unprotected areas which may be disregarded in assessing the separation distances from the boundry Diagram 20 - Unprotected areas which may be disregarded in assessing the separation distances from the boundry
                    • Diagram 21 - The effect of a conopy on separation distance Diagram 21 - The effect of a conopy on separation distance
                    • Diagram 22 - Permitted unprotected areas for Method 1 Diagram 22 - Permitted unprotected areas for Method 1
                    • Diagram 23 - Limitations on spacing and size of plastic rooflights having a Class 3 (National class) or Class D-s3, d2 (European class) or TP(b) lower surface Diagram 23 - Limitations on spacing and size of plastic rooflights having a Class 3 (National class) or Class D-s3, d2 (European class) or TP(b) lower surface
                    • Diagram 24 - Turning facilities Diagram 24 - Turning Facilities
                    • Table 1 - Classification of linings Table 1 - Classification of linings
                    • Table 3 - Maximum nominal internal diameter of pipes passing through a fire separating element Table 3 - Maximum nominal internal diameter of pipes passing through a fire separating element
                    • Table 3 - Maximum nominal internal diameter of pipes passing through a fire separating element Table 3 - Maximum nominal internal diameter of pipes passing through a fire separating element
                    • Table 4 - Permitted unprotected areas for Method 2 Table 4 - Permitted unprotected areas for Method 2
                    • Table 5 - Limitations on rood coverings Table 5 - Limitations on rood coverings
                    • Table 6- Class 3 (National class) or Class D-s3, d2 (eurpean class) plstic rooflights - limitations on use and boundary distance Table 6- Class 3 (National class) or Class D-s3, d2 (eurpean class) plstic rooflights - limitations on use and boundary distance
                    • Table 7 - TP (a) and TP (b) plastic rooflights- limitations on use and boundary distance Table 7 - TP (a) and TP (b) plastic rooflights- limitations on use and boundary distance
                    • Table A8 - Typical performance ratings of some generic materails and products Table A8 - Typical performance ratings of some generic materails and products
                    • Table A1 - Specific provisions of test for fire resistance of elements of structure etc Table A1 - Specific provisions of test for fire resistance of elements of structure etc
                    • Table A1 continued Table A1 continued
                    • Table A2 - Minimum periods of fire resistance for dwellinghouses Table A2 - Minimum periods of fire resistance for dwellinghouses
                    • Table A3 - Limitations on fire - protecting suspended ceilings (see Table A1, Note 4) Table A3 - Limitations on fire - protecting suspended ceilings (see Table A1, Note 4)
                    • Table A4 - Limitations on the use of uninsulated glazed elements on escape routes Table A4 - Limitations on the use of uninsulated glazed elements on escape routes
                    • Table A5 - Notional designations of roof coverings Table A5 - Notional designations of roof coverings
                    • Table A6 - Use and definitions of non-combustible materials Table A6 - Use and definitions of non-combustible materials
                    • Table A7 - Use and definitions of materails of limited combustibillty Table A7 - Use and definitions of materails of limited combustibillty
                    • Table A8 - Typical performance ratings of some generic materails and products Table A8 - Typical performance ratings of some generic materails and products
                    • Table B1 Provision for fire doors Table B1 Provision for fire doors
                    • Table  C1 - Height of top storey in building Table C1 - Height of top storey in building
                    • Table D1 - Classification of Purpose Groups Table D1 - Classification of Purpose Groups

                    Appendix A Performance of materials, products and structures

                    Performance of materials, products and structures

                    1. Introduction
                      1. Fire resistance
                        1. Roofs
                          1. Reaction to fire
                            1. Non-combustible materials
                              1. Materials of limited combustibility
                                1. Internal linings

                                  Introduction

                                  1. Much of the guidance in this document is given in terms of performance in relation to British or European Standards for products ormethods of test or design or in terms of European Technical Approvals. In such cases the material, product or structure should:
                                  a. be in accordance with a specification or design which has been shown by test to be capable of meeting that performance; or Note: For this purpose, laboratories accredited by the United Kingdom Accreditation Service (UKAS) for conducting the relevant tests would be expected to have the necessary expertise. b.have been assessed from test evidence against appropriate standards, or by using relevant design guides, as meeting that performance; or Note: For this purpose, laboratories accredited by UKAS for conducting the relevant tests and suitably qualified fire safety engineers might be expected to have the necessary expertise. For materials/products where European standards or approvals are not yet available and for a transition period after they become available, British standards may continueto be used. Any body notified to the UK Government by the Government of another member state of the European Union as capable of assessing such materials/products against the relevant British Standards, may also be expected to have the necessary expertise. Where European materials/products standards or approvals are available, any body notified to the European Commission as competent to assess such materials or products against the relevant European standards or technical approval can be considered to have the appropriate expertise. 3.where tables of notional performance are included in this document, conform with an appropriate specification given in these tables; or 4.in the case of fire-resisting elements:
                                  • conform with an appropriate specification given in Part II of the Building Research Establishment’s report Guidelines for the construction of fire resisting structural elements (BR 128, BRE 1988); or
                                  • be designed in accordance with a relevant British Standard or
                                  Note 1: Different forms of construction can present different problems and opportunities for the provision of structural fire protection. Further information on some specific forms of construction can be found in Timber – BRE 454 Multi-storey timber frame buildings – a design guide 2003 (ISBN: 1 86081 605 3) Steel – SCI P197 Designing for structural fire safety: A handbook for architects and engineers 1999 (ISBN: 1 85942 074 5) Note 2: Any test evidence used to substantiate the fire resistance rating of a construction should be carefully checked to ensure that it demonstrates compliance that is adequate and applicable to the intended use. Small differences in detail (such as fixing method, joints, dimensions and the introduction of insulation materials etc.) may significantly affect the rating. 2. Building Regulations deal with fire safety in buildings as a whole. Thus they are aimed at limiting fire The aim of standard fire tests is to measure or assess the response of a material, product,structure or system to one or more aspects of fire behaviour. Standard fire tests cannot normally measure fire hazard. They form only one of a number of factors that need to be taken into account. Other factors are set out in this publication.  

                                  Fire resistance

                                  3. Factors having a bearing on fire resistance, that are considered in this document, are:

                                  • fire severity;
                                  • building height; and
                                  • building
                                  4. The standards of fire resistance given are based on assumptions about the severity of fires and the consequences should an element Fire severity is estimated in very broad terms from the use of the building (its purpose group), on the assumption that the building contents (which constitute the fire load) are similar for buildings in the same use. A number of factors affect the standard of fire resistance specified. These are:
                                  • the amount of combustible material per unit of floor area in various types of building (the fire load density);
                                  • the height of the top floor above ground, which affects the ease of escape and of firefighting operations and the consequences should large scale collapse occur;
                                  • occupancy type, which reflects the ease with which the building can be evacuated quickly;
                                  • whether there are basements, because the lack of an external wall through which to vent heat and smoke may increase heat build-up and thus affect the duration of a fire, as well as complicating firefighting; and
                                  • whether the building is of single storey construction (where escape is direct and structural failure is unlikely to precede evacuation).Because the use of buildings may change, a precise estimate of fire severity based on the fire load due to a particular use may be misleading. Therefore if a fire engineering approach of this kind is adopted the likelihood that the fire load may change in the future needs to be considered.
                                  5. Performance in terms of the fire resistance to be met by elements of structure, doors and other forms of construction is determined by reference to either: (National tests) BS 476 Fire tests on building materials and structures, Parts 20-24: 1987,i.e. Part 20 Method for determination of the fire resistance of elements of construction (general principles), Part 21 Methods for determination of the fire resistance of loadbearing elements of construction, Part 22 Methods for determination of the fire resistance of non-loadbearing elements of construction, Part 23 Methods for determination of the contribution of components to the fire resistance of a structure and Part 24 Method for determination of the fire resistance of ventilation ducts (or to BS 476-8:1972 in respect of items tested or assessed prior to 1 January 1988); or (European tests) Commission Decision 2000/367/EC of 3rd May 2000 implementing Council Directive 89/106/EEC as regards the classification of the resistance to fire performance of construction products, construction works and parts
                                  • Note: The latest version of any standard may be used provided that it continues to address the relevant requirements of the Regulations.All products are classified in accordance with BS EN 13501-2:2007, Fire classification of construction products and building elements Classification using data from fire resistance tests (excluding products for use in ventilation systems). BS EN 13501-3:2005, Fire classification of construction products and building elementsClassification using data from fire resistance tests on components of normal building service installations (other than smoke control systems). BS EN 13501-4:2007, Fire classification of construction products and building elements Classification using data from fire resistance tests on smoke control systems. The relevant European test methods under BS EN 1364, 1365, 1366 and 1634 are listed in Appendix G.
                                  Table A1 gives the specific requirements for each element in terms of one or more of the following performance criteria:
                                  1. resistance to collapse (loadbearing capacity), which applies to loadbearing elements only, denoted R in the European classification of the resistance to fire performance;
                                  2. resistance to fire penetration (integrity), denoted E in the European classification of the resistance to fire performance; and
                                  3. resistance to the transfer of excessive heat (insulation), denoted I in the European classification of the resistance to fire
                                  Table A2 sets out the minimum periods of fire resistance for elements of structure. Table A3 sets out criteria appropriate to the suspended ceilings that can be accepted as contributing to the fire resistance of a floor. Table A4 sets out limitations on the use of uninsulated fire-resisting glazed elements. These limitations do not apply to the use of insulated fire-resisting glazed elements. Information on tested elements is frequently given in literature available from manufacturers and trade associations. Information on tests on fire-resisting elements is also given in such publications as: Association for Specialist Fire Protection Fire protection for structural steel in buildings 4th Edition (ISBN: 1 87040 925 6

                                  Roofs

                                  6. Performance in terms of the resistance of roofs to external fire exposure is determined by reference to either:

                                  1. (National tests) BS 476-3:2004 External fire exposure roof tests; or
                                  2. (European tests) Commission Decision 2005/823/EC amending Decision 2001/671/EC establishing a classification system for the external fire performance of roofs and roof coverings.
                                  Constructions are classified within the National system by 2 letters in the range A to D, with an AA designation being the best. The first letter indicates the time to penetration; the second letter a measure of the spread of flame. Constructions are classified within the European system as BROOF(t4), CROOF(t4), DROOF(t4), EROOF(t4)or FROOF(t4) (with BROOF(t4) being the highest performance and FROOF(t4) being the lowest) in accordance with BS EN 13501-5:2005, Fire classification of construction products and building elements Classification using test data from external fire exposure to roof tests. BS EN 13501-1 refers to four separate tests. The suffix (t4) used above indicates that Test 4 is to be used for the purposes of this Approved Document. Some roof covering products (and/or materials) can be considered to fulfil all of the requirements for the performance characteristic “external fire performance” without the need for testing, subject to any national provisions on the design and execution of works being fulfilled. These roof covering products are listed in Commission Decision 2000/553/EC of 6th September 2000 implementing Council Directive 89/106/EEC as regards the external fire performance of roof coverings. In some circumstances roofs, or parts of roofs, may need to be fire-resisting, for example if used as an escape route or if the roof performs the function of a floor. Such circumstances are covered in Sections 2, 4 and 6. Table A5 gives notional designations of some generic roof coverings.

                                  Reaction to fire

                                  7. Performance in terms of reaction to fire to be met by construction products is determined by Commission Decision 200/147/EC of 8th February 2000 implementing Council Directive 89/106/EEC as regards the classification of the reaction to fire performance of construction products. Note: The designation of xxxx is used for the year reference for standards that are not yet published. The latest version of any standard may be used provided that it continues to address the relevant requirements of the Regulations. All products, excluding floorings, are classified as †A1, A2, B, C, D, E or F (with class A1 being the highest performance and F being the lowest) in accordance with BS EN 13501-1:2007, Fire classification of construction products and building elements, Part 1 – Classification using data from reaction to fire tests. The relevant European test methods are specified as follows, BS EN ISO 1182:2002, Reaction to fire tests for building products – Non-combustibility test. BS EN ISO 1716:2002, Reaction to fire tests for building products – Determination of the gross calorific value. BS EN 13823:2002, Reaction to fire tests for building products – Building products excluding floorings exposed to the thermal attack by a single burning item. BS EN ISO 11925-2:2002, Reaction to fire tests for building Products, Part 2 – Ignitability when subjected to direct impingement of a flame. BS EN 13238:2001, Reaction to fire tests for building products – conditioning procedures and general rules for selection of substrates.  

                                  Non-combustible materials

                                  8. Non-combustible materials are defined in Table A6 either as listed products, or in terms of performance:

                                  1. (National classes) when tested to BS 476- 4:1970 Non-combustibility test for materials or BS 476-11:1982 Method for assessing the heat emission from building products; or
                                  2. (European classes) when classified as class A1 in accordance with BS EN 13501-1:2007, Fire classification of construction products and building elements, Part 1-Classification using data from reaction to fire tests when tested to BS EN ISO 1182:2002, Reaction to fire tests for building products – Non- combustibility test and BS EN ISO 1716:2002 Reaction to fire tests for building products – Determination of the gross calorific value.
                                  Table A6 identifies non-combustible products and materials and lists circumstances where their use is necessary.

                                  Materials of limited combustibility

                                  9. Materials of limited combustibility are defined in Table A7:

                                  1. (National classes) by reference to the method specified in BS 476: Part 11:1982; or
                                  2. (European classes) in terms of performance when classified as class A2-s3, d2 in accordance with BS EN 13501-1:2007, Fire classification of construction products and building elements, Part 1 – Classification using data from reaction to fire tests when tested to BS EN ISO 1182:2002, Reaction to fire tests for building products – Non- combustibility test or BS EN ISO 1716:2002 Reaction to fire tests for building products – Determination of the gross calorific value and BS EN 13823:2002, Reaction to fire tests for building products – Building products excluding floorings exposed to the thermal attack by a single burning item.
                                  Table A7 also includes composite products (such as plasterboard) which are considered acceptable and where these are exposed as linings they should also meet any appropriate flame spread rating.

                                  Internal linings

                                  Internal linings 10. Flame spread over wall or ceiling surfaces is controlled by providing for the lining materials or products to meet given performance levels in tests appropriate to the materials or products involved. 11.Under the National classifications, lining systems which can be effectively tested for ‘surface spread of flame’ are rated for performance by reference to the method specified in BS 476- 7:1971 Surface spread of flame tests for materials, or 1987 Method for classification of the surface spread of flame of products, or 1997 †            The classes of reaction to fire performance of A2, B, C, D and E are accompanied by additional classifications related to the production of smoke (s1, s2, s3) and/or flaming droplets/particles (d0, d1, d2). Method of test to determine the classificationof the surface spread of flame of products under which materials or products are classified 1, 2, 3 or 4 with Class 1 being the highest. Under the European classifications, lining systems are classified in accordance with BS EN 13501-1:2007, Fire classification of construction products and building elements, Part 1 – Classification using data from reaction to fire tests. Materials or products are classified as A1, A2, B, C, D, E or F, with A1 being the highest. When a classification includes “s3, d2”, it means that there is no limit set for smoke production and/or flaming droplets/particles. 12. To restrict the use of materials which ignite easily, which have a high rate of heat release and/ or which reduce the time to flashover, maximum acceptable ‘fire propagation’ indices are specified, where the National test methods are being These are determined by reference to the method specified in BS 476-6:1981 or 1989 Method of test for fire propagation of products. Index of performance (I) relates to the overall test performance, whereas sub-index (i1) is derived from the first three minutes of test. 13. The highest National product performance classification for lining materials is Class This is achieved if a material or the surface of a composite product is either:

                                  1. composed throughout of materials of limited combustibility; or
                                  2. a Class 1 material which has a fire propagation index (I) of not more than 12 and sub-index (i1) of not more than
                                  Note: Class 0 is not a classification identified in any British Standard test. 14. Composite products defined as materials of limited combustibility (see paragraph 9 above and Table A7) should in addition comply with the test requirement appropriate to any surface rating specified in the guidance on requirements B2, B3 and 15. The notional performance ratings of certain widely used generic materials or products are listed in Table A8 in terms of their performance in the traditional lining tests BS 476 Parts 6 and 7 or in accordance with BS EN 13501-1:2007, Fire classification of construction products and building elements, Part 1 – Classification using data from reaction to fire 16. Results of tests on proprietary materials are frequently given in literature available from manufacturers and trade Any reference used to substantiate the surface spread of flame rating of a material or product should be carefully checked to ensure that it is suitable, adequate and applicable to the construction to be used. Small differences in detail, such as thickness, substrate, colour, form, fixings, adhesive etc, may significantly affect the rating. To reduce the testing burden on manufacturers, BS EN 13238 Reaction to fire tests for building products – conditioning procedures and general rules for the selection of standard substrates, defines a number of standard substrates that produce test results representative of different end use applications. The standard substrate selected for testing should take account of the intended end use applications (field of application) of the product and represent end use substrates which have a density of at least 75% of its nominal density. The reaction to fire classification achieved during testing is only valid when the product is used within this field of application i.e. when the product is fixed to a substrate of that class in its end use. Standard substrates include, Gypsum plasterboard (BS EN 520) with a density of 700+/-100 Kg/m3, Calcium silicate board (BS EN 14306) 870+/-50 Kg/m3   and Fibre cement board 1800+/-200 Kg/m3. Note: Standard calcium silicate board is not representative of gypsum plasterboard end use (due to the paper layer), but would be representative of most gypsum plasters (with densities of more than 650 Kg/m3). Classifications based on tests using a plasterboard substrate would also be acceptable for products bonded to a gypsum plaster end use substrate.

                                  • 1 Gallery floors with no alternative exit Diagram 1 Gallery floors with no alternative exit
                                  • 2 Flat where all habitable rooms have direct access to an entrance hall Diagram 2 Flat where all habitable rooms have direct access to an entrance hall
                                  • 3 Flat with restricted travel distance from furthest point to entrance Diagram 3 Flat with restricted travel distance from furthest point to entrance
                                  • 4 Flat with an alternative exit but where all habitable rooms have no direct acess to an entrance hall Diagram 4 Flat with an alternative exit but where all habitable rooms have no direct access to an entrance hall
                                  • 5 Multi-storey flat with alternative exits from each habitable room except at entrance level 5 Multi-storey flat with alternative exits from each habitable room except at entrance level
                                  • 6 Multi-storey flat with protected entrance hall and landing Diagram 6 Multi-storey flat with protected entrance hall and landing
                                  • 7 Flats served by one common stair,png Diagram 7 Flats served by one common stair
                                  • 8 Flats served by more than one common stair 8 Flats served by more than one common stair
                                  • 9 Common escape route in small single stair building Diagram 9 Common escape route in small single stair building
                                  • 10 Travel distance in dead-end condition 10 Travel distance in dead-end condition
                                  • 11 Alternative escape routes 11 Alternative escape routes
                                  • 12 Inner room and access room 12 Inner room and access room
                                  • 13 Exits in a central core Diagram 13 Exits in a central core
                                  • 14 Open Connections Diagram 14 Open Connections
                                  • 15 Merging flows at final exit Diagram 15 Merging flows at final exit
                                  • 16 Subdivision of corridors Diagram 16 Subdivision of corridors
                                  • 17 Dead-end corridors Diagram 17 Dead-end corridors
                                  • 18 Maximum travel distances in a small two or three storey premises with a single protected stair to each storey Diagram 18 Maximum travel distances in a small two or three storey premises with a single protected stair to each storey
                                  • 19 Progressive horizontal evacuation in care homes Diagram 19 Progressive horizontal evacuation in care homes
                                  • 20 Refuge formed by compartmentation Diagram 20 Refuge formed by compartmentation
                                  • 21 Refuge formed in a protected stairway Diagram 21 Refuge formed in a protected stairway
                                  • 22 Max travel distance in a small three storey premises with a single stair to each storey Diagram 22 Max travel distance in a small three storey premises with a single stair to each storey
                                  • 23 Max travel distance in a small two storey premises with a single open stair Diagram 23 Max travel distance in a small two storey premises with a single open stair
                                  • 24 External protection to protected stairways Diagram 24 External protection to protected stairways
                                  • 25 Fire resistance of areas adjacent to external stairs 25 Fire resistance of areas adjacent to external stairs
                                  • 26 Lighting diffuser in relation to ceiling Diagram 26 Lighting diffuser in relation to ceiling
                                  • 27 Layout restrictions on Class 3 plastic roofflights TP-b rooflights and TP b lighting diffusers Diagram 27 Layout restrictions on Class 3 plastic rooflights TP-b rooflights and TP b lighting diffusers
                                  • 27a Layout restrictions on small Class 3 plastic rooflights TP b rooflights and lighting diffusers Diagram 27a Layout restrictions on small Class 3 plastic rooflights TP b rooflights and lighting diffusers
                                  • 28 Compartment floors illustration of guidance in paragraph 8.16 Diagram 28 Compartment floors illustration of guidance in paragraph 8.16
                                  • 29 Compartment walls and compartment floors with reference to relevant paragraphs in Section 8 Diagram 29 Compartment walls and compartment floors with reference to relevant paragraphs in Section 8
                                  • 30 Junction of compartment wall with roof Diagram 30 Junction of compartment wall with roof
                                  • 31 Protected shafts Diagram 31 Protected shafts
                                  • 32 Uninsulated glazed screen separating protected shaft from lobby or corridor Diagram 32 Uninsulated glazed screen separating protected shaft from lobby or corridor
                                  • 33 Provisions for cavity barriers Diagram 33 Provisions for cavity barriers
                                  • 34 Cavity wall excluded from provisions for cavity barriers Diagram 34 Cavity wall excluded from provisions for cavity barriers
                                  • 35 Fire-resisting ceiling below concealed space Diagram 35 Fire-resisting ceiling below concealed space
                                  • 36 Provisions for cavity barriers in double-skinned insulated roof sheeting Diagram 36 Provisions for cavity barriers in double-skinned insulated roof sheeting
                                  • 37 Pipes penetrating structure Diagram 37 Pipes penetrating structure
                                  • 38 Enclosure for drainage or water supply pipes Diagram 38 Enclosure for drainage or water supply pipes
                                  • 39 Flues penetrating compartment walls or floors Diagram 39 Flues penetrating compartment walls or floors
                                  • 40 Provisions for external surfaces or walls Diagram 40 Provisions for external surfaces or walls
                                  • 41 Relevant boundary Diagram 41 Relevant boundary
                                  • 42 Notional boundary Diagram 42 Notional boundary
                                  • 43 Status of combustible surface material as unprotected area Diagram 43 Status of combustible surface material as unprotected area
                                  • 44 Unprotected areas which may be disregarded in assessing the separation distance from the boundary Diagram 44 Unprotected areas which may be disregarded in assessing the separation distance from the boundary
                                  • 45 The effect of a canopy on separation distance Diagram 45 The effect of a canopy on separation distance
                                  • 46 Permitted unprotected areas in small residential buildings Diagram 46 Permitted unprotected areas in small residential buildings
                                  • 47 Limitations on spacing and size of plastic rooflights having a Class 3 or Class D-s3 d2 or TP b lower surface Diagram 47 Limitations on spacing and size of plastic rooflights having a Class 3 or Class D-s3 d2 or TP b lower surface
                                  • 48 Example of building footprint and perimeter Diagram 48 Example of building footprint and perimeter
                                  • 49 Relationship between buildings and hardstanding access roads for high reach fire appliances Diagram 49 Relationship between buildings and hardstanding access roads for high reach fire appliances
                                  • 50 Turning facilities Diagram 50 Turning facilities
                                  • 51 Provision of firefighting shafts Diagram 51 Provision of firefighting shafts
                                  • 52 Components of a firefighting shaft Diagram 52 Components of a firefighting shaft
                                  • 53 Fire-resisting construction for smoke outlet shafts Diagram 53 Fire-resisting construction for smoke outlet shafts
                                  • C1 Measurement of door width Diagram C1 Measurement of door width
                                  • C2 Cubic capacity Diagram C2 Cubic capacity
                                  • C3 Area Diagram C3 Area
                                  • C4 Height of building Diagram C4 Height of building
                                  • C5 Number of storeys Diagram C5 Number of storeys
                                  • C6 Height of top storey in buildingC6 Height of top storey in building Diagram C6 Height of top storey in building
                                  • C7 Free area of smoke ventilators Diagram C7 Free area of smoke ventilators
                                  • D1 Classification of Purpose Groups Diagram D1 Classification of Purpose Groups
                                  • E1 Recessed car parking areas Diagram E1 Recessed car parking areas
                                  • Table 1 Limitations on distance of travel in common areas of blocks of flats - see par 2.23 Table 1 Limitations on distance of travel in common areas of blocks of flats - see par 2.23
                                  • Table 2 Limitations on travel distance Table 2 Limitations on travel distance
                                  • Table 3 Minimum number of escape routes and exits from a room tier or storey Table 3 Minimum number of escape routes and exits from a room tier or storey
                                  • Table 4 Widths of escape routes and exits Table 4 Widths of escape routes and exits
                                  • Table 5 Maximum distances of travel in small premises with a protected stair Table 5 Maximum distances of travel in small premises with a protected stair
                                  • Table 6 Minimum widths of escape stairs Table 6 Minimum widths of escape stairs
                                  • Table 7 Capacity of a stair for basements and for simultaneous evacuation of the building Table 7 Capacity of a stair for basements and for simultaneous evacuation of the building
                                  • Table 8 Minimum width of stairs designed for phased evacuation Table 8 Minimum width of stairs designed for phased evacuation
                                  • Table 9 Provisions for escape lighting Table 9 Provisions for escape lighting
                                  • Table 10 Classification of linings Table 10 Classification of linings
                                  • Table 11 Limitations applied to thermoplastic rooflights and lighting diffusers in suspended ceilings and Class 3 plastic rooflights Table 11 Limitations applied to thermoplastic rooflights and lighting diffusers in suspended ceilings and Class 3 plastic rooflights
                                  • Table 12 Maximum dimensions of building or compartment - non-residential buildings Table 12 Maximum dimensions of building or compartment - non-residential buildings
                                  • Table 13 Maximum dimensions of cavities in non-domestic buildings - purpose Groups 2-7 Table 13 Maximum dimensions of cavities in non-domestic buildings - purpose Groups 2-7
                                  • Table 14 Maximum nominal internal diameter of pipes passing through a compartment wall-floor - see par 10.5 onwards Table 14 Maximum nominal internal diameter of pipes passing through a compartment wall-floor - see par 10.5 onwards
                                  • Table 15 Permitted unprotected areas in small buildings or compartments Table 15 Permitted unprotected areas in small buildings or compartments
                                  • Table 16 Limitations on roof coverings Table 16 Limitations on roof coverings
                                  • Table 17 Class 3 or Class D-s3 d2 plastic rooflights limitations on use and boundary distance Table 17 Class 3 or Class D-s3 d2 plastic rooflights limitations on use and boundary distance
                                  • Table 18 TP a and TP b plastic rooflights limitations on use and boundary distance Table 18 TP a and TP b plastic rooflights limitations on use and boundary distance
                                  • Table 19 Fire and rescue service vehicle access to buildings excluding blocks of flats not fitted with fire mains Table 19 Fire and rescue service vehicle access to buildings excluding blocks of flats not fitted with fire mains
                                  • Table 20 Typical fire and rescue service vehicle access route specification Table 20 Typical fire and rescue service vehicle access route specification
                                  • Table A1 Specific provisions of test for fire resistance of elements of structure etc Table A1 Specific provisions of test for fire resistance of elements of structure etc
                                  • Table A1 continued Table A1 continued
                                  • Table A2 Minimum periods of fire resistance Table A2 Minimum periods of fire resistance
                                  • Table A3 Limitations on fire-protecting suspended ceilings - see Table A1 Note 4 Table A3 Limitations on fire-protecting suspended ceilings (see Table A1 Note 4)
                                  • Table A4 Limitations on the use of uninsulated glazed elements on escape routes Table A4 Limitations on the use of uninsulated glazed elements on escape routes]
                                  • Table A5 Notional designations of roof coverings Table A5 Notional designations of roof coverings
                                  • Table A6 Use and definitions of non-combustible materials Table A6 Use and definitions of non-combustible materials
                                  • Table A7 Use and definitions of materials of limited combustibility Table A7 Use and definitions of materials of limited combustibility
                                  • Table A8 Typical performance rating of some generic materials and products Table A8 Typical performance rating of some generic materials and products
                                  • Table B1 Provisions for fire doors Table B1 Provisions for fire doors
                                  • Table C1 Floor space factors Table C1 Floor space factors
                                  • Table D1 Classification of Purpose Groups Table D1 Classification of Purpose Groups
                                  • Table Maximum dimensions of building or compartment - non-residential buildings Table Maximum dimensions of building or compartment (non-residential buildings)