Access To Buildings Other Than Dwellings (M1/M2)
Ramped access
Note: Where there appears to be a conflict between the guidance in Part M and Part K, Part M takes precedence; see the Notes to the Requirements.
Design considerations
1.19 If site constraints necessitate an approach of 1:20 or steeper , an approach incorporating ramped access should be provided. Ramps are beneficial for wheelchair users and people pushing prams, pushchairs and bicycles.
1.20 Gradients should be as shallow as practicable, as steep gradients create difficulties for some wheelchair users who lack the strength to propel themselves up a slope or have difficulty in slowing down or stopping when descending.
1.21 Ramps are not also necessarily safe and convenient for ambulant disabled people. For example, some people who can walk but have restricted mobility find it more difficult to negotiate a ramp than a stair. In addition, adverse weather foundations increase the risk of slipping on a ramp. It is therefore beneficial to have steps as well as a ramp.
1.22 Some people need to be able to stop frequently; for instance to regain strength or breath, or to ease pain.
1.23 Wheelchair users need adequate space to stop on landings, to open and pass through doors without having to reverse into circulation routes or to face the risk of rolling back down slopes.
1.24 Some people have a weakness on one side. This leads to a requirement for support at both sides of ramps.
1.25 If the total rise of a ramped approach is too high, it can be unacceptably firing for wheelchair users and some people with walking difficulties, even if a number of rest landings are provided.
Note: Guidance is given in BS 8300 on:
- lighting ramped access.
Provisions
1.26 A ramped access will satisfy Requirement M1 or M2 if:
a. |
either it is readily apparent or the approach to it is clearly sign-posted |
b. |
the gradient of a ramp flight and its going between landings are in accordance with Table 1 and Diagram 3; |
c. |
no flight has a going greater than 10m, or a rise of more than 500mm; |
Table 1 Limits for ramp gradients |
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Diagram 3 Relationship of ramp gradient to the going of a flight. |
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d. |
there is an alternative means of access for wheelchair users, e.g. a lift, when the total rise is greater than 2m; |
e. |
it has a surface width between walls upstands or kerbs of at least 1.5m; |
f. |
the ramp surface is slip resistant, especially when wet, and of a colour that contrasts visually with that of the landings; |
g. |
the frictional characteristics of the ramp and landing surfaces are similar; |
h. |
there is a landing at the foot and head of the ramp at least 1.2m long and clear of any door swings or other obstructions; |
i. |
any intermediate landings are at least 1.5m long and clear of any door swings or other obstructions; |
j. |
intermediate landings at least 1800mm wide and 1800mm long are provided as passing places when it is not possible for a wheelchair user to see from one end of the ramp to the other or the ramp has three flights or more; |
k. |
all landings are level, subject to a maximum gradient of 1:60 along their length and a maximum cross-fall gradient of 1:40; |
l. |
there is a handrail on both sides; |
m. |
there is a kerb on the open side of any ramp or landing at least 100mm high, which contrasts visually with the ramp or landing in addition to any guarding required under Part K; |
n. |
clearly sign-posted steps are provided, in addition, when the rise of the ramp is greater than 300mm (equivalent to 2 x 150mm steps). |
Stepped Access
Note: Where there appears to be a conflict between the guidance in Part M and Part K, Part M takes precedence; see the Notes to the Requirements.
Design Considerations
1.27 People with impaired sight risk tripping or losing their balance if there is no warning that steps provide a change in level. The risk is most hazardous at the head of a flight of steps when a person is descending.
1.28 The warning should be placed sufficiently in advance of the hazard to allow time to stop and not be so narrow that it might be missed in a single stride.
1.29 Materials for treads should be able to appreciate easily where to place their feet by highlighting nosings and avoiding open rises.
1.31 People who wear callipers or who have stiffness in hip or knee joints are particularly at risk of tripping or catching their feet beneath nosings. People with a weakness on one side or with a sight impairment need the dimensions of the tread to be sufficient for them to be able to place their feet square onto it. If the going is towards the upper end of the dimensional range, the flight may rise to a greater height without the need for an intermediate landing, as the tread is sufficiently deep to allow a person to stand and rest at any point within the flight. It should be noted that excessive rounding of nosings reduces the effective going.
Note:Guidance is given in BS 8300 on:
- lighting stepped access; and
- slip resistance (Annex C).
Provisions
1.33 A stepped access will satisfy Requirement M1 or M2 if:
a. |
a level landing is provided at the top and bottom of each flight; |
b. |
the unobstructed length of each landing is not less than 1200mm; |
c. |
a "corduroy" hazard warning surface is provided at top and bottom landings of a series of flights to give advance warning of a change in level in accordance with Diagram 4; |
Diagram 4 Stepped access - key dimensions and use of hazard warning surface
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d. |
where there is a side access onto an intermediate landing a "corduroy" hazard warning surface 400mm deep is provided either on the intermediate landing 400mm from both upper and lower flights, if there is sufficient space to accommodate the surface outside the line of the side access, or within the side access 400mm from the intermediate landing if there is a continuous handrail opposite the side access; |
e. |
no doors swing across landings; |
f. |
it has flights whose surface width between enclosing walls, strings or upstands is not less than 1.2m; |
g. |
there are no single steps; |
h. |
the rise of a flight between landings contains no more than 12 risers for a going of less than 350mm and no more than 18 risers for a going of 350mm or greater (see Diagram 5); |
i. |
all nosings are made apparent by means of a permanently contrasting material 55mm wide on both the tread and riser; |
j. |
the projection of a step nosing over the tread below is avoided but, if necessary, not more than 25mm (see Diagram 6); |
Diagram 5 External steps and stairs - key dimensions |
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k. |
the rise and going of each step is consistent throughout a flight; |
l. |
the rise of each step is between 150mm and 170mm, except adjacent to existing buildings where, due to dimensional constraints, the care for a different rise is agreed with the building control body; |
m. |
the going of each step is between 280mm and 425mm; |
o. |
there is a continuous handrail on each side of a flight and landings; |
p. |
additional handrails divide the flight into channels not less than 1m wide and not more than 1.8m wide where the overall unobstructed width is more than 1.8m. |
Note: In respect of 1.33(l) and (m), for school buildings, the preferred dimensions are a rise of 150mm, and a going of 280mm.
Handrails to external stepped and ramped access
Design Considerations
1.34 People who have physical difficulty in negotiating change of level need the help of a handrail that can be gripped easily, is comfortable to touch, and, preferably, provide good forearm support.
1.35 Handrails should be spaced away from the wall and rigidly supported in a way that avoids impeding finger grip.
Diagram 6 Examples of acceptable step profiles and key dimensions for external stairs |
1.36 Handrails should be set at heights that are convenient for all users of the building and should extend safely beyond the top and bottom of a flight of steps, or a ramp, to give both stability and warning of the presence of a change in level. Consideration should be given to the provision of a second handrail on stairs in a wide range of building types, and particularly in schools, for use by children and people of short stature.
Provisions
1.37 Handrailing to external ramped and stepped access will satisfy Requirement M1 or M2 if:
a. |
the vertical height to the top of the upper handrail from the pitch line of the surface of a ramp, or a flight of steps, is between 900mm and 1000mm, and from the surface of a landing is between 900 and 1100mm (see Diagram 5); |
b. |
where there is full height structural guarding, the vertical height to the top of a second lower handrail from the pitch line of the surface of a ramp, or a flight of steps, is 600mm, where provided. |
c. |
it is continuous across the flights and landings of ramped or stepped access. |
d. |
it extends at least 300mm horizontally beyond the top and bottom of a ramped access, or the top and bottom nosing of a flight or flights of steps, while not projecting into an access route; |
e. |
it contrasts visually with the background against which it is seen, without being highly reflective; |
f. |
its surface is slip resistant and not cold to the touch, in areas where resistance to vandalism or low maintenance are key factors, use of metals with relatively low thermal conductivity may be appropriate; |
g. |
it terminates in a way that reduces the risk of clothing being caught; |
h. |
its profile is either circular with a diameter of 32 and 50mm, or non-circular, 50mm wide and 39mm deep having rounded edges with a radius a minimum of 15mm (See Diagram 7); |
i. |
it protrudes no more than 100mm into the surface width of the ramped or stepped access where this would impinge on the stair width requirement of Part B1; |
j. |
there is a clearance of between 60 and 75mm between the handrail and any adjacent wall surface; |
k. |
there is a clearance of at least 50mm between a cranked support and the underside of the handrail; |
l. |
its inner face is located no more than 50mm beyond the surface width of the ramped or stepped access. |
Diagram 7 Handrail design |
Hazards on access routes
Design considerations
1.38 Features of a building that occasionally obstruct an access route, particularly if they are partically transparent and therefore indistinct, or cause a danger overhead, should not present a hazard to building users.
Provisions
1.39 Requirement M1 or M2 will be satisfied in relation to hazards on access routes where Approved Document K, sections 6 and 10 are complied with.
Note: Diagram 8 has been moved to Approved Document K, Section 10, all other numbering remains the same.