D1.1 This Part sets out the required standards for Regulation 12.
D1.2 The standards apply to all buildings.
FIRE RESISTANCE
D2.1*
a. Every element of structure in a building must have a fire resistance of at least that in Table 1 to this Standard, applied or modified as specified for particular elements in Table 2, or as stated in any standard.
b. The period of fire resistance of a floor may include that of an associated suspended fire resisting ceiling where the fire resisting ceiling is either imperforate, with no openings, or complies with Table 3 to this Standard with no openings other than those permitted by D5.1 and D5.3, and any access hatch or door to the cavity formed by the ceiling maintains the fire resistance of the ceiling when closed. The fire resistance of the floor shall be the fire resistance of the floor/ceiling assembly.
c. Where an element of structure serves more than one purpose, or attracts more than one standard of fire resistance, the more onerous standard is to apply.
d. Where an element of structure provides support to another element of structure to which a higher standard applies it must meet that standard,
except -
i. a. above does not apply to a part of a single storey building which does not form part of, or supports -
A. a separating wall, compartment wall, or the enclosing structure of a protected zone; or
B. an external wall or part of an external wall which is allowed to form part of an unprotected area by D6; or
ii. a., c. and d. above do not apply to a suitably designed part of a steel portal frame in a single storey building.
Notes:
In determining fire resistance -
1. a beam which is built into, or forms part of a floor, is to be taken to be part of the floor;
2. a column which is built into, and does not project beyond either face of a wall, is to be taken to be part of the wall;
3. methods of verifying compliance with performance standards are given in the Appendix to this Part.
D2.1
Table 1 to D2.1: Periods of fire resistance for elements of structure in a building or compartment according to its height, depth, storey area and cubic capacity (See D3.2)
|
Purpose group or sub-group |
Form of building or part of building |
The lowest basement storey at a depth of [Note 5] (m) |
The topmost storey of a building or the topmost storey of any compartment at a height of (m) |
Area of any storey within building or compartment [Note 1] (m2) |
Cubic capacity of building or compartment [Note 1] (m3) |
Minimum period of fire resistance [Notes 6 and 7] (mins) |
|
|
1A |
(flats and maisonettes) |
any |
§ |
<7.5 |
no limit |
no limit |
30 |
|
<4.5 |
<18.0 |
no limit |
no limit |
60 |
|||
|
>4.5 |
>18.0 |
no limit |
no limit |
90 [3] |
|||
|
1B |
(houses) |
any |
§ |
<7.5 |
no limit |
no limit |
30 |
|
any |
>7.5 |
no limit |
no limit |
60 [4] |
|||
|
1C |
(houses) |
any |
§ |
<4.5 |
no limit |
no limit |
30 |
|
2A |
(institutional) |
any |
§ |
<7.5 |
<1500 |
<3000 |
30 |
|
any |
>7.5 |
<1500 |
<8500 |
90 |
|||
|
2B |
(other residential) |
any |
§ |
<7.5 |
<2000 |
<4200 |
30 [2] |
|
any |
>7.5 |
<2000 |
<8500 |
60 |
|||
|
any |
>7.5 |
<2000 |
<14000 |
90 |
|||
|
3 |
(offices) |
any |
§ |
<7.5 |
<4600 |
<4200 |
30 [2] |
|
any |
>7.5 |
<4600 |
<14000 |
60 |
|||
|
any |
>7.5 |
<4600 |
<28000 |
90 |
|||
|
4 |
(shops and commercial) [Note 8] |
any |
§ |
<7.5 |
<2800 |
<2200 |
30 [2] |
|
any |
>7.5 |
<2800 |
<4200 |
60 |
|||
|
any |
>7.5 |
<2800 |
<7100 |
150 |
|||
|
5A |
(high hazard assembly) |
any |
§ |
<7.5 |
<1900 |
<4900 |
30 [2] |
|
any |
>7.5 |
<1900 |
<14000 |
60 |
|||
|
any |
>7.5 |
<1900 |
no limit |
120 |
|||
|
5B |
(low hazard assembly) |
any |
§ |
<7.5 |
no limit |
<5600 |
30 [2] |
|
any |
>7.5 |
no limit |
<14000 |
60 |
|||
|
any |
>7.5 |
no limit |
<21000 |
90 |
|||
|
6A |
(high hazard industrial) |
single storey |
§ |
any |
<1400 |
no limit |
30 [2] |
|
§ |
any |
<7000 |
no limit |
60 |
|||
|
§ |
any |
<33000 |
no limit |
120 |
|||
|
more than one storey |
any |
any |
<2800 |
<1700 |
60 |
||
|
any |
any |
<2800 |
<8500 |
90 |
|||
|
any |
any |
<2800 |
<28000 |
120 |
|||
|
6B |
(low hazard industrial) |
single storey |
§ |
any |
<9000 |
no limit |
30 [2] |
|
§ |
any |
<93000 |
no limit |
90 |
|||
|
more than one storey |
any |
any |
<7500 |
<8500 |
60 |
||
|
any |
any |
<7500 |
>84000 |
90 |
|||
|
any |
any |
<7500 |
no limit |
120 |
|||
|
7A |
(high hazard storage) |
single storey |
§ |
any |
<100 |
no limit |
60 |
|
§ |
any |
<500 |
no limit |
180 |
|||
|
§ |
any |
<1000 |
no limit |
240 |
|||
|
more than one storey |
any |
any |
<500 |
<1000 |
60 |
||
|
any |
any |
<500 |
<2000 |
180 |
|||
|
any |
any |
<500 |
<4200 |
240 |
|||
|
7B |
(low hazard storage) |
single storey |
§ |
any |
<1000 |
no limit |
30 [2] |
|
§ |
any |
<2500 |
no limit |
60 |
|||
|
§ |
any |
<14000 |
no limit |
120 |
|||
|
more than one storey |
any |
any |
<2800 |
<1400 |
60 |
||
|
any |
any |
<2800 |
<8500 |
120 |
|||
|
any |
any |
<2800 |
<21000 |
180 |
|||
|
7C |
(open-sided car parks) |
any |
§ |
any |
no limit |
no limit |
15 |
Notes:
[1] Except in the case of purpose groups 1 and 2, the storey area or cubic capacity, or both, may be doubled for a stated period of fire resistance if the building or compartment is provided with an appropriate fire control system. The stated period of fire resistance for elements of structure must not be reduced in this case (see Notes 6 and 7).
[2] At least 60 minutes for a compartment wall or a compartment floor to a compartment used as an alternative means of escape as provided for by E3.1.
[3] Reduced to 60 minutes for any non-loadbearing separating wall between flats or maisonettes.
[4] Reduced to 30 minutes for a floor wholly within a dwelling which does not contribute to the support of the building as a whole. No reduction for a basement storey.
[5] The floor over a basement storey, or if there is more than 1 basement storey the floor over the topmost basement storey, must meet the requirements for the ground storey and upper storeys where that period of fire resistance is higher than that for the basement storey. Otherwise the period of fire resistance of the floor over a basement storey must be that of the relevant basement storey.
[6] In a basement or part of a basement in a building of purpose group 3-7 other than purpose sub-group 7C with an appropriate automatic fire control system, the minimum period of fire resistance may where appropriate be reduced by 30 minutes to not less than 60 minutes.
[7] In a building or part of a building with an appropriate fire control system otherwise than in Note [6] above, the minimum period of fire resistance may where appropriate be reduced by 30 minutes to not less than 30 minutes, except for those elements of structure for which a minimum period of fire resistance is required in Table 2 (see Note [1] above), and the elements of structure which support those elements of structure (see D2.1c.).
[8] Unlimited storey area and cubic capacity in a building of purpose group 4 which has an appropriate fire control system and is either
i. single storey and complies with D7.2, or
ii. an enclosed shopping centre with a mall on one or two storeys which complies with D7.5.
Key:
< means not more than.
> means more than.
§ means that the minimum period of fire resistance for a basement
storey is 60 minutes.
DIAGRAM TO TABLE 1 TO D2.1
Diagram
Table 2 to D2.1: Application and modification of particular requirements for periods of fire resistance
|
Element of structure |
Minimum period (minutes) |
Exposure |
|||
|
Loadbearing capacity[2] |
Integrity |
Insulation |
|||
|
1. |
Structural frame, beam or column other than in a single storey building or single storey part of a building or a member forming part of or supporting only a roof structure(see D2.1e) |
[1] |
none |
none |
Faces exposed to inside |
|
2. |
Loadbearing wall which is not also an external wall, separating wall, compartment wall or the enclosing structure of a protected zone (see 4, 5, 6 or 9) |
[1] |
none |
none |
each side separately |
|
3. |
Internal loadbearing wall in a single storey building which is not also a seperating wall, compartment wall or the enclosing structure of a protected zone |
none |
none |
none |
Not applicable |
|
4.
|
External wall other than any part of the wall which is permitted to be an unprotected area by D6 |
||||
|
(a) any part which is less than 1m but not less than 500mm from a relevant boundary other than as provided for by D6.1 |
[1] |
[1] |
[1] |
inside |
|
|
(b) any part which is 1m or more from a relevant boundary other than as provided for D6.1 |
[1] |
[1] |
15 |
inside |
|
|
5. |
Separating wall |
|
|
|
|
|
(a) General |
[1] (min 60) |
[1] (min 60) |
[1] (min 60) |
each side separately |
|
|
(b) shared residential accommodation |
min 30 |
min 30 |
min 30 |
each side separately |
|
|
(c) a wall between a house and its garage |
min 30 |
min 30 |
min 30 |
from the garage side |
|
|
6. |
Compartment wall |
|
|
|
|
|
(a) General (see D3.2) |
[1] |
[1] |
[1] |
each side separately |
|
|
(b) Place of special fire risk |
[1] (min 60) |
[1] (min 60) |
[1] (min 60) |
||
|
7.
|
Floor |
|
|
|
|
|
(a) lowest floor of a building |
none |
none |
none |
not applicable |
|
|
(b) floor of upper storey of house of purpose sub-group 1C (but not over a garage) and any floor within a maisonette, but not if the floor contributes to the support of the building |
30 |
15 |
15 |
underside |
|
|
(c) a floor between a house and its garage |
min 30 |
min 30 |
min 30 |
from the garage side |
|
|
(d) separating floor |
[1] (min 60) |
[1] (min 60) |
[1] (min 60) |
underside |
|
|
(e) gallery |
none |
none |
none |
not applicable |
|
|
(f) catwalk or openwork floor |
none |
none |
none |
not applicable |
|
|
(g) any other floor (including a compartment floor other than a floor to a place of special fire risk, access deck, and a floor over a garage) |
[1] |
[1] |
[1] |
underside |
|
|
(h) compartment floor to a place of special fire risk |
[1] (min 60) |
[1] (min 60) |
[1] (min 60) |
inside risk place |
|
|
8. |
Roof or access deck |
|
|
|
|
|
any part forming an escape route (see E3.2) |
min 60 |
min 60 |
min 60 |
from the underside |
|
|
9. |
Enclosing structure of a protected zone not being a roof or an external wall but including the floor other than that of the lowest storey - |
||||
|
(a) General (see D3.3) |
min 60 |
min 60 |
min 60 |
walls:each side separately floors: from the underside |
|
|
(b) Shared residential accommodation (see D7.1) |
min 30 |
min 30 |
min 30 |
walls: each side separately floors: from the underside |
|
|
10. |
Protected enclosure (see D3.4) |
none |
min 30 |
min 30 |
each side separately |
|
11. |
Fire-fighting shaft |
[1] (min 60) |
[1] (min 60) |
[1] (min 60) |
from side remote from shaft |
|
12. |
Smoke venting shaft |
[1] |
[1] |
[1] |
each side |
|
13. |
Enclosing structure of a lift well not being in a protected zone |
[1] |
[1] |
[1] |
each side separately |
|
14. |
Enclosing structure of a lift well within a protected zone |
30 |
30 |
30 |
inside lift well |
|
15. |
Cavity barrier |
|
|
|
|
|
(a) cavity barrier 1m x 1m or larger |
none |
30 |
15 |
each side separately |
|
|
(b) cavity barrier less than 1m x 1m |
none |
30 |
none |
each side separately |
|
|
16. |
Fire resisting ceiling dispensing with cavity barrier |
none |
30 |
30 |
underside |
|
17. |
A wall or screen dividing a corridor for smoke control |
none |
30 |
none |
each side separately |
|
18. |
Fire door |
none |
none |
Each side separately when fitted in its frame, other than lift doors (from outside only) |
|
|
(a) in a separating wall between a flat or maisonette and a protected lobby or a protected zone |
30[S] |
||||
|
(b) in a separating wall not described in (a) above |
|
[3][S] |
|
|
|
|
(c) in a compartment wall or compartment floor (hatch or trap-door) |
[3][S] |
||||
|
(d) in an enclosing structure of a protected zone |
|
[3][S] |
|
|
|
|
(e) to an external escape stair or open access balcony where an external escape route passes the fire door to the exit of the dwelling |
30 |
||||
|
(f) dividing a corridor for smoke control |
|
20[S] |
|
|
|
|
(g) within a dwelling of purpose sub-group 1A or 1B where there is a fire resistance requirement |
20 |
||||
|
(h) in an enclosing structure of a lift well where the lift well is not in a protected zone |
[3] |
||||
|
(i) in an enclosing structure of a lift well between a lift well and protected zone |
30 |
||||
|
(j) to a fire-fighting shaft |
|
[3][S] |
|
|
|
|
(k) in an enclosing structure of an accommodation stair or escalator within an un-compartmented building or compartment |
30[S] |
||||
|
(l) in any other situation including a door in a cavity barrier |
|
30[S] |
|
|
|
|
|
|
|
|
||
|
19. |
Fire shutter actuated by a fusible link |
none |
[3] |
[4] |
each side separately |
|
20. |
Wall or floor separating private solid waste storage accommodation from the rest of the building in purpose group 1 |
none |
30 |
30 |
walls:from each side separately floors: from the underside |
Key
[1] Period of fire resistance set out in Table 1.
[2] Applies to loadbearing elements only.
[3] Period of fire resistance for the wall or floor (see D3.7 c. iii.)
in which the fire door or fire shutter is situated. Where
the period of fire resistance for the wall in which the fire door
is situated does not exceed 120 minutes, the period of fire resistance
for the wall. Where the period of fire resistance
for the wall exceeds 120 minutes, half the period of fire resistance
for the wall but not less than 120 minutes. This concession does not apply
to fire shutters.
[4] Where in a wall the fire shutter requires to be insulated the
minimum period of insulation must be that for the wall (see D3.6).
[S] Smoke control fire door.
Table 3 to D2.1: Suspended fire-resisting ceiling contributing to fire resistance of a floor
|
Height of topmost storey of building or compartment (m) |
Type of floor |
If the required fire resistance of the floor/ceiling assembly is (minutes) |
Then the construction and performance of the ceiling must be as below |
|
Not more than 11 |
non-compartment |
not more than 60 |
surface of ceiling exposed within the cavity not lower than Class 1; no requirement for supports for the ceiling |
|
compartment |
not more than 30 |
surface of ceiling exposed within cavity not lower than Class 1; ceiling and supports and fixings for the ceiling non-combustible |
|
|
not more than 60 |
surface of ceiling exposed within the cavity not lower than Class 0; ceiling and supports and fixings for the ceiling non-combustible |
||
|
More than 11 |
any |
not more than 60 |
surface of ceiling exposed within the cavity not lower than Class 0, imperforate ceiling; and supports and fixings for the ceiling non-combustible |
|
No limit |
any |
more than 60 |
ceiling non-combustible and imperforate; supports and fixings for the ceiling non-combustible; no access panel permitted |
Note:
The surface classification of materials is given in Table 2 to
(E6.1).
NON-COMBUSTIBILITY
D2.2 Every part of a building specified in the table to this
Standard must be of non-combustible materials,
except -
a. a part specifically excepted in the table; or
b. a floor finish, wall or ceiling lining, or an external cladding, which does not contribute to the minimum fire resistance required for the part it covers.
Table to D2.2: Non-combustible materials
|
Part required to be constructed of non-combustible materials |
Exceptions |
|
Compartment floor complying with Table 1 to D2.1 |
None |
|
Compartment floor complying with D3.2 |
in a building of purpose sub-group 2A other than a hospital |
|
Separating floor |
1. in a building of purpose sub-group 1A or shared residential accommodation with no storey at a height of more than 11m, other than over solid waste storage accommodation. |
|
2. between a shop or office and a dwelling above the shop or office
in the same occupation and where - |
|
|
3 above a pend in a building of purpose group 1, where the ceiling of the pend is constructed of non-combustible materials and the floor immediately above the pend has at least 60 minutes fire resistance. |
|
|
4. between dwellings and shared residential accommodation. |
|
|
Compartment wall in a building of purpose sub-group 2A |
in a building of purpose sub-group 2A other than a hospital |
|
Compartment wall or a compartment floor separating a lift well from the remainder of the building |
None |
|
Separating wall |
a wall in a building with no storey at a height of more than 11m, containing a structural frame of combustible material and any insulant if any surface exposed to a cavity is Class 1 and the internal lining has a surface Class 1 or higher and the wall contains no pipes, wires or other services, and is between - |
|
a. houses or houses and their ancillary garages or shared residential accommodation; or |
|
|
b. flats or maisonettes, where the wall does not form part of the enclosure to a common stair or the enclosure of solid waste storage accommodation; or |
|
|
c. flats or maisonettes and an escape stair enclosure, where the wall is constructed of masonry or concrete on the stair side of the wall. |
|
|
d. between dwellings and shared residential accommodation. |
|
|
External wall on or less than 1m from a relevant boundary |
1. a wall in a building of purpose group 1 or in shared residential accommodation with no storey at a height of more than 11m containing a structural frame of combustible material with a non-combustible external cladding. |
|
2. any thermal insulation in a wall in a building. |
|
|
Enclosing structure of a protected zone |
1. in shared residential accommodation. |
|
2. in any other building where it comprises - |
|
|
3. in a building of purpose sub-group 1A where a wall, not being a separating wall, enclosing an escape stair is constructed of masonry or concrete on the stair side. |
|
|
Escape stair or ramp including the floor of a protected lobby |
1. any handrail on an escape stair |
|
2. an escape stair which complies with E4.6(a) or (b). |
Notes:
1. A beam or column which forms part of a wall or floor that is required to be non-combustible, and any supporting structure, must also be non-combustible.
2. The surface classification of materials is given in Table 2 to (E6.1).