Section 11 Special provisions for car parks and shopping complexes

Special provisions for car parks and shopping complexes

  1. Introduction
    1. Car parks
      1. General principles
        1. Open-sided car parks
          1. Car parks which are not open-sided
            1. Natural ventilation
              1. Mechanical ventilation
              2. Shopping complexes

                Introduction

                11.1This section describes additional considerations which apply to the design and construction of car parks and shopping complexes.

                Car parks

                General principles

                11.2Buildings or parts of buildings used as parking for cars and other light vehicles are unlike other buildings in certain respects which merit some departures from the usual measures to restrict fire spread within buildings. Those are:

                • aThe fire load is well defined; and
                • bWhere the car park is well ventilated, there is a low probability of fire spread from one storey to another. Ventilation is the important factor and, as heat and smoke cannot be dissipated so readily from a car park that is not open-sided, fewer concessions are made. The guidance in paragraphs 11.3 to 11.6 is concerned with three ventilation methods: open-sided (high level of natural ventilation), natural ventilation and mechanical ventilation.

                Open-sided car parks

                11.3If the building, or separated part containing the car park, complies with the following provisions it may be regarded as an open-sided car park for the purposes of fire resistance assessment in Appendix A, Table A2. The provisions are that:

                • athere should not be any basement storeys;
                • beach storey should be naturally ventilated by permanent openings at each car parking level, having an aggregate vent area not less than 1/20th of the floor area at that level, of which at least half (1/40th) should be equally provided between two opposing walls;
                • cwhere 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).
                • dif the building is also used for any other purpose, the part forming the car park is a separated part and the fire resistance of any element of structure that supports or carries or gives stability to another element in the other part of the building should be no less than the minimum period of fire resistance for the elements it supports; and
                • eall materials used in the construction of the building, compartment or separated part should be non-combustible, except for:
                  • iany surface finish applied to a floor or roof of the car park, or within any adjoining building, compartment or separated part to the structure enclosing the car park, if the finish meets all relevant aspects of the guidance on requirements B2 and B4;
                  • iiany fire door;
                  • iiiany attendant's kiosk not exceeding 15m2 in area; and
                  • ivany shop mobility facility.

                Car parks which are not open-sided

                11.4Where car parks do not have the standard of ventilation set out in paragraph 11.3(b), they are not regarded as open-sided and a different standard of fire resistance is necessary (the relevant provisions are given in Appendix A, Table A2).

                Such car parks still require some ventilation, which may be by natural or mechanical means, as described in paragraphs 11.5 or 11.6 below.

                Natural ventilation

                11.5Where car parks that are not open-sided are provided with some, more limited, natural ventilation, each storey should be ventilated by permanent openings (which can be at ceiling level) at each car parking level. These should have an aggregate free vent area not less than 1/40th of the floor area at that level, of which at least half should be split equally and provided between two opposing walls (1/160th on each side). (See Approved Document F Ventilation for additional guidance on normal ventilation of car parks.)

                Mechanical ventilation

                11.6In most basement car parks and in enclosed car parks, it may not be possible to obtain the minimum standard of natural ventilation openings set out in paragraph 11.5. In such cases a system of mechanical ventilation should be provided as follows:

                • athe system should be independent of any other ventilating system (other than any system providing normal ventilation to the car park) and be designed to operate at 10 air changes per hour in a fire condition. (See Approved Document F Ventilation for guidance on normal ventilation of car parks);
                • bthe system should be designed to run in two parts, each part capable of extracting 50% of the rates set out in (a) above and designed so that each part may operate singly or simultaneously;
                • ceach part of the system should have an independent power supply which would operate in the event of failure of the main supply;
                • dextract points should be arranged so that 50% of the outlets are at high level and 50% at low level; and
                • ethe fans should be rated to run at 300degC for a minimum of 60 minutes and the ductwork and fixings should be constructed of materials having a melting point not less than 800degC.

                For further information on equipment for removing hot smoke, refer to BS EN 12101-3:2002.

                An alternative method of providing smoke ventilation from enclosed car parks is given BS 7346-7:2006

                Shopping complexes

                11.7Whilst the provisions in this document about shops should generally be capable of application in cases where a shop is contained in a single separate building, the provisions may not be appropriate where a shop forms part of a complex. These may include covered malls providing access to a number of shops and common servicing areas. In particular, the provisions about maximum compartment size may be difficult to meet, bearing in mind that it would generally not be practical to compartment a shop from a mall serving it. To a lesser extent, the provisions about fire resistance, walls separating shop units, surfaces and boundary distances may pose problems.

                11.8To ensure a satisfactory standard of fire safety in shopping complexes, alternative measures and additional compensatory features to those set out in this document are appropriate. Such features are set out in Sections 5 and 6 of BS 5588-10:1991 and the relevant recommendations of those sections should be followed.

                • 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)