Nov 152011
 

Safety is Paramount when it comes to Stairways-Part M

Stairs-PartM

It stands to reason that stairways must be safe. If stairs are too steep, and they don’t have railings, or if screens and balustrades are not strong and secure, people may fall with disastrous consequences.

What the National Building Regulations say about Stairs and Stairways

“Any stairway, including any wall, screen, railing or balustrade to such stairway, shall:

(a) be capable of safely sustaining any actions which can reasonably be expected to occur and in such a manner that any local damage (including cracking) or deformation do not compromise its functioning;

(b) permit safe movement of persons from floor to floor; and

(c) have dimensions appropriate to its use.”

What this means is that stairways, in addition to all the elements relating to them, must be properly designed. This takes us back to Part B of the NBR, which deals with structural design.

Like everything else, stairways must be designed to provide the strength, stability, serviceability and durability required for use. It is imperative that they are built so that any accidental overload won’t cause the stairway to collapse. It is also vital to takes steps to ensure that people won’t fall off the structure. If the sides of the stairs don’t have railings or screens this CAN happen – and it does (sadly) happen.

In addition to these general requirements, there are fire requirements that must be adhered to. These are outlined in Part T of SANS 10400 – Fire Protection, but when it comes to houses, those that are relevant mainly relate to basics (including the materials used to build your home). For instance you don’t have to have fire escapes, exit doors, escape routes, and that kind of thing.

SANS 10400 Stairways – Part M

As always, the South African National Standards give a good rundown on how we should build to ensure that we “satisfy” the legislation. The most recent Standard was published in April 2011; and it contains new guidelines that relate to both masonry stairways and timber stairways.

You will find Part M of the legislation towards the end of Standard, on Page 11.

It should be read in conjunction with several other Standards, including SANS 2001-CC1, -CC2, and -CM1 that deal with structural concrete works, minor concrete works and masonry walling; SANS 1460, Laminated timber (glulam); and SANS 1783-2, that deals with stress-graded structural timber and timber for frame wall construction; as well as several other parts of SANS 10400, specifically Part A (general principles), Part B (structural design), Part K (walls), Part S (facilities for people with disabilities), and Part T (fire protection). This is important because, for instance:

  • Part S reduces the rise of the step (as indicated in this part), increases the width of stairways and the length of landings. It also has a requirement that solid risers should be used where stairs overlap the next lower tread, and another that specifies the need for handrails on both sides of the stairway.
  • Part T increases the standard width of stairways as indicated in this part, disallows the use of spiral stairways, and requires solid risers for all buildings except those defined in Part A as D4 (a plant room that contains mechanical or electrical services that are necessary for the running of a building, and are usually left unattended).

Requirements of this particular Standard that relate to dimensions specify that:

  • there must be sufficient headroom above any stairway: at least 2,1 m measured vertically from the pitch line of the staircase (see drawing below)

    stairways

    Minimum headroom allowed on stairways

  • stairs need to be wide enough for safe use, usually not less than 750 mm (see drawing below)
  • the going (depth of the tread) and width of treads must be at least 250 mm (see drawing below)

    stairways

    Allowable minimum dimensions of treads and risers

  • treads of stairways that do not have solid risers must overlap the next tread by at least 25 mm (see drawing above)
  • landings serving two flights in a straight line need to be at least 900 mm long and at least as wide as the flight of stairs
  • there shouldn’t be a vertical rise that is greater than 3 m between landings
  • single step risers shouldn’t be more than 200 mm
  • doors cannot open onto stairways unless it’s onto a landing – and the landing then needs to be at least the width of the door (which must not obstruct people using the stairs)

Sometimes the dimensions of risers and going of treads vary in a flight of stairs. This variation should not be more than 6 mm. Further, dimensions of each individual step can be checked for safety by adding the dimension of the going to 2 x the height of the riser. This should be at least 570 mm and no more than 650 mm.

Tapered treads and winders (which are are steps that are narrower on one side than the other and used to change direction of the stairs without landings) are most common in spiral stairways. If they don’t form part of a spiral staircase, they must be designed to comply with the minimum tread and riser dimensions shown in the drawing above, and have a minimum going of 125 mm. The angle between successive risers (measured horizontally) must be constant (see drawing below).

stairways

To check the variation in going between tapered treads, measure each tread at the same distance from the narrow end

Stairways that incorporate winders – defined by the SANS as a “tapered tread that has a going of at least 50 mm and which is used in conjunction with non-tapered treads in a single flight” –  are permitted in our homes as long as there are no more than three of them, and the winder may not turn through more than 90 degrees.

Spiral stairways are defined as a “succession of tapered treads forming a curved stairway which extends as a single flight from one floor or landing to another”. These must be no wider than 800 mm and may not be used as an emergency route. There are also restrictions in terms of certain buildings where they may not be used, including theatres and other entertainment venues, schools, sports facilities, places of worship, exhibition bass, jails, hospitals and health care facilities, offices, hotels, dormitories and hospitality venues.

Prevention Against Falling

It should be common sense, but people don’t always see it that way, because stairs don’t always LOOK good with railings!

Essentially what SANS tell us is that:

If a flight of stairs is more than three risers high, it could be dangerous, especially if toddlers and old people use it. This is why it is essential to have some sort of protection to prevent falling.

This can be in the form of:

  • a secure wall
  • a screen of some sort
  • railings or a balustrade – all of which should be at least 1 m high

Other issues include “openings”. If a child can fall through a gap in the railings, or if someone falls and their leg or foot gets stuck in the gap, it could end up really badly. The opening specification is similar to that which relates to swimming pool fencing: it shouldn’t allow anything with more than a 100 mm diameter to pass through it.

Handrails are also an important element. If a flight of steps continues for more than about five risers, there should be a handrail of some sort. And any sort of handrail MUST be securely fixed to the wall, screen, railing, balustrade or whatever! In some instances, for example when the stairs are wide (more than 1,1 m), it might be necessary to have a railing on either side.

If a screen is made of glass, it is vital that the glass used complies with the relevant SANS.

Timber Stairways

There are several clauses that relate specifically to timber stairs in SANS 10400 Part M (Edition 3, 2011). This section was previously not covered in the “deemed to satisfy” regulations.

Stringer Beams

Stringer beams support treads, and where these are not be wider than 1,2 m in double- and single-storey domestic residences and dwelling houses, they should be at least 48 mm x 225 mm. Grade 5 timber should be used and it should not be excessively warped.

Timber Treads

These must be at least 36 mm thick. Since timber stairways are designed in different ways, the options are that they may be:

  • built into masonry walls with a minimum end bearing of 90 mm
  • supported on a steel angle cleat that has minimum dimensions of 50 mm x 50 mm x 4 mm
  • bolted to a wall with two masonry anchors per clear according to the manufacturer’s instructions

If anchors are used and embedded into a Grade 20 concrete (which will be 20 MPa), these anchors must have  “a safe working load in sheer of not less than 1,25 kN, certified by the manufacturer”.

Materials Used for Timber Steps

Building Materials and Tests in general are covered in Part A of the National Building Regulations. In terms of timber, it should be treated against termites and wood borer as well as protected against fungal decay in terms of SANS 10005. For consumers, the important thing to look for is the product certification mark of a body that has been certified by the SA National Accreditation System.

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Glazing

  133 Responses to “Stairways”

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  1. In process of building house. We planning a floating staircase which carries both architect and engineer’s approval. It has solid wall with required hand rail on one side. Is it possible to have the floating/cantilevered side open?

    • I do not think that you can. But your architect is supposed to know the SANS so the design they give should not violate the regulations and he is the best one to answer the question.

  2. We are acting on behalf of an Owner who is handicapped whereby his left leg and arm are very weak as he suffered polio at very young age.

    He owns a Flat in Portobella Place, Morning Side, Johannesburg which he as owned for many years which he utilizes when visiting Johannesburg as he is based currently based in Rwandu.

    His mobility of recent has deteriorated, and he is experiencing difficulty when using the staircase to reach his Unit which is situated on the 3rd Floor. The person is now 60 years of age.

    We have approached the Trustees with a request to please install Handrails on the staircase which will allow safe access to and from his Unit.

    Their initial response is negative and rude in that they are asking why he purchased the Unit on the Third floor rather than a ground Unit in the first instance! The fact is that when he bought the Unit many years ago he condition was of such that he was able to use the staircase without the difficulty which he is now experiencing.

    Your advise in terms of Regulations Governing such a situation would be greatly appreciated.

    With kind Regards,

    Johann van Heeden.

    • Apologies for the delay in replying. It would seem on the face of it that they have no right to make comments like that or to be rude in any way. They are in contravention and must rectify the situation. Please read this post: facilities-for-disabled-people

  3. Hi

    Are there any regulations prohibiting the use of access control doors in a staircases? Example being between for instance floor 1 and 2, if floors 2-4 are occupied by the same company.

    As an extra note, the door will only be access controlled going upwards and quick release mechanism going downwards.

    Thanks

    • This is not a Building Regulations issue. It sounds to me like a security issue that needs to be sorted out between those using the building – and the landlord or building owner.

      • Thanks Penny, my mistake I should have mentioned that my concern is regarding the regulation for installing access control in a staircase which is also used as a fire evacuation route.

        I have found the answers I needed.

        Regards

        • What was the answer? I don’t think there’s anything to stop one using a staircase that is used as an exit route, providing nothing blocks it and all the other regulations (width – exit doors etc) are complied with.

  4. Hi

    Can anyone tell me what the SANS regulation is for the contrasting on stair treads to make them visual for the partially sighted.

    Thank you
    Lee

    • Lee there are several related references that might help you.
      C.2.4 Visual information
      “By creating clarity in the built environment, a level of safety that helps to minimize the risk of injury to persons with visual impairments can be achieved.”
      Only one para refers directly to stairways:
      “Colour, tone and luminance contrast should be used to aid the identification of critical surfaces. Externally, critical surfaces include guiding walls, steps, rails and textured guidance surfaces. Internally, critical surfaces that require an effective LRV level are ceilings, walls, floors, stairways, doors and significant fixtures and fittings.”
      This appears in another section:
      “Uneven surfaces, steps with irregular risers or open risers on flights of stairs are likely to cause persons with visual impairments to trip and injure themselves. Quality of workmanship is extremely important in avoiding gaps between surface finishes, raised thresholds, and to ensure that all steps have uniform risers.”
      And this is the part that refers directly to stairways – though it doesn’t answer your question I don’t think. Unfortunately I don’t have a copy of SANS 784 referred to.
      4.9 Stairways
      4.9.1 Stairways shall comply with the requirements of SANS 10400-M, SANS 10400-T and the
      following requirements:
      a) the width of any stairway, measured to an enclosing wall or balustrade, shall be at least 900 mm;
      b) a landing that serves two flights of stairs in the same straight line shall be of length at least 1 100 mm;
      c) the rise of each tread step shall be of the same height and shall not exceed 170 mm;
      d) solid risers shall be provided in all accessible routes;
      e) a stairway shall be provided with handrails on both sides of the stairway in accordance with the requirements of 4.10;
      f) Themaximumheightallowedinaflightofstairs,betweenlandings,shallnotexceed1,530m;
      g) The stairway shall not include any winders (as defined in SANS 10400-M);
      h) No spiral stairway shall form part of an accessible route.
      4.9.2 Nosingsshalleffectivelycontrastwiththeirimmediatesurroundings.Theminimumdimensionsof each nosing shall be 40 mm × 40 mm.
      NOTE Further guidance on contrast and methods of measurement is provided in SANS 784.
      4.9.3 Outdoor stairs and outdoor approaches to stairs shall be so designed that water will not accumulate on walking surfaces.
      4.9.4 Tactile guidance, where provided, shall be in accordance with the relevant provisions of SANS 784.”

  5. Hi. Are the occupants of a building permitted to use an external fire escape stairway on a daily basis as a means of moving between different floors when there is no emergency?

    • Lindy I can’t find anything that says this is not permitted. I imagine the most important issue would be maintenance.

  6. Hi There

    Can you please tell me what the building regulations say for stairs that the public
    use. I need to know the tread, height and the width ?

  7. Is there any regulation that defines the minimum height of a riser?

    • Yes Miles there is and you will find it on this page.

      • Hi Penny.

        Thanks for getting back to me! But I can’t seem to find the answer “on this page” though…

        Possibly you misread my question: I was asking if there is a MINIMUM requirement!

        I know that Part B refers to a maximum riser of 200mm and requires twice the riser plus the going to be between 570 and 650mm. And that Part S refers to a maximum riser of 170mm.

        I can’t find a regulation that states what the minimum riser may be. So, I have assumed that as long as the riser/going calculation stays between 570 and 650mm, it will be acceptable.

        The case in point requires four steps with 141mm risers and the going is currently 300mm. The riser/going calculation results in a figure of 582mm. Also: this is not for an internal or external staircase forming part of a building. Rather it is stairs on a dedicated pedestrian route on the site between residential buildings.

        Regards,

        MILES

        • Sorry: not Part B. I mean Part M!

        • Hi Miles, Load shedding got in the way a bit today 🙁 I have double checked with my Inspector contact and there is no minimum riser height. So for instance if you have a 2 metre length with a total height of 200mm then you can have 4 x 50mm risers with a going on each of 500mm. Hope this helps 🙂

  8. I notice that you do not mention the exclusion of occupancy H3 and H4 from requiring a handrail. Has this been removed?

    • Keith, I presume this is the clause you are referring to… It has not been removed.
      4.3 Prevention of Falling
      “4.3.2 Any flight of stairs which contains more than five risers shall be provided with at least one continuous handrail extending the full length of such flight, provided that this requirement shall not apply to any building classified as H4, or within individual dwelling units in an occupancy classified as H3.”

      • Thanks Penny, that is what I am referring to, but I see that it is not mentioned on this website. Quite a significant omission.

  9. Hi

    I was wondering if you could tell me if it is possible to use a ladder, or a steeper incline for loft spaces ? I see the uk regs allow for this, is there anything in sans ?

    Thanks

    • Hi Byron, I do not see anything directly related to this nor could I find any vague reference to it. I’m sure that for access to a storage area a ladder will be fine. If you want to make permanent stairs, the regulations do say that the rise (height) of any tread should not exceed 200mm. And the going and width of any tread will not be less than 250 mm, provided that where the stairway does not have solid risers, each tread shall overlap the next lower tread by not less than 25 mm. Now the steeper you go then the treads overlap dangerously so what they do is make a cut-out on each alternate step (shaped like a sort of paddle) so that your foot does not get caught on the way up or slip off a narrow ledge on the way down. See the picture below:
      (Pic courtesy Karina stairs Canada)

  10. hi, your comments about the April 2011 legeslative changes indicates; Part T ….. disallows the use of spiral stairways… We wanted to instal a spiral staircase in a holiday home in the mageliesburg hills, near rustenburg. are spiral staircases now forbidden, or are they still alowed for domestic living situations.

    thanks
    phil

    • Hi Phil, The Regulations Part M – Stairways says:
      4.2.10 Stairways incorporating winders shall be permitted only in dwelling houses and within
      individual dwelling units…
      A guest house it would seem is classed as occupancy “H5 – Hospitality” and in that case is not allowed.
      Part T – Fire protection does not allow any spiral stairway to be used as an escape route.

  11. My client wants a spiral stair. The diameter of the hole is 1450mm so we could fit a steel & timber stair of 1400mm diameter which gives us tread widths of 650mm (after subtracting the 100mm diam. centre pole). The floor to floor height is 3370mm.

    When trying to get a stair that works in terms of headroom under the landing I get risers of about 241mm and tread with a depth of 220mm (measured at 250mm from the inside edge of the handrail). This means the line that one is likely to walk is steeper than 45 degrees! If I put in more steps on the stair I quickly get a headroom problem as one goes under the landing at the top of the stair.

    Before we issue the drawing to manufacture the stair I need to know if SANS 10400 or any other reg. give riser and tread dimensions for spiral stairs?

    Thanks!

  12. Could you please clarify the reason for limiting the width of a spiral staircase to 0.8m?
    We would like to have a central pole with treads of 1200mm length extending both sides of the central pole.
    Treads will be supported from below.

    • Celeste we do not set the standards, but it is based on safety options, and an engineer’s specifications. If you want to build something that does not comply you will need an agrement certificate!

    • Seems like a regulation that has not been well thought out and there are no guidelines of how to achieve a workable spiral stair. The are plenty of examples of spiral stairs that are wider than 800mm and, in my experience, these have been comfortable and safe to use.

      • Hi David, I have seen a few spiral staircases with the dimensions that you have given. I am not an expert in this field so if you don’t mind I will put you in contact with someone who I am sure will help you. Rob & Sandra Blackbeard of Steel Studio – Sandra@steelstudio.co.za

  13. Want to build a wooden steps/and steel railings extending over wall with a length of 4.1m and going from the floor to a height of 2.8m in a straight line. Must there be a landing in as well or can it only be the risers?

    • Doreen Part M of SANS 10400 states: “No flight of stairs shall have a vertical rise greater than 3 m between landings.” i.e. Every 3 m there needs to be a landing. But it can be in a straight line, as long as:
      “Any landing serving two flights in the same straight line shall
      a) have a length of not less than 900 mm, and
      b) have a width of not less than that of such flights.”

  14. Hi There,

    I am leasing two dwelling which form a duplex. The garage forms part of the building, were the there is a stairway leading from the garage to the second level dwelling. It’s about twenty steps up. I have requested the owner to install hand rails, were he said sure you can install yourself. I feel it’s not my responsibility to pay for this, as any additional fixtures will form part of the building, and I will not be refunded. Plus my wife, me and my daughter have now fallen down these steps, and if there were hand rails, it would have definitely prevented this. Were he replies to, can’t you walk standing up?

    Next time, we might not be so lucky…
    Is there a forum that protects me? Regulation that he has to adhere to?

    I am concerned that I am being bullied by being said to it’s our fault.

    • Etienne, Railings for stairways must be at least 1 m high, and if the flight is more than five risers high it must have a continuous handrail that extend the full length of the flight. It should also be “securely fixed to such wall, screen, railing or balustrade at a height of not less than 850 mm and not more than 1 m measured vertically from the pitch line to the upper surface of the handrail”.
      If you have already fallen down the stairs you already have a claim against the landlord.
      If I were you I would contact the local authority and tell them the story – and ask them to notify the owner that he must by law install hand rails.
      It certainly does sound as if you are being bullied.

      • Hi Penny,

        I have the same situation as Etienne and appreciate your reponse – where in the South African Building Regulations can I quote this to my agent?, i.e. which para of the regulations are these specific requirements stated.

        Thank you

        • Hi Natalie, Penny has been away for a few days, apologies. The answer to your question is SANS 10400 Part-M chapter “4.3 Prevention against falling”

  15. Can someone please answer this? I appied with the owner of a building (he is still busy building), to hire one of the premises (for a shop). This is a double story with space on the side on top. He told me that I have to pay for the staircase even though I am only hiring the space from him. Also I have to pay for the dry walling. Is this true? When I leave the place after a year or two I cannot take the staircase with me for I have paid for it? Is there somewhere a law which states that the person hiring must also pay for such things?

    • Nope Erika – no law. He’s trying his luck. It’s all got to do with supply and demand. If he doesn’t have a staircase then the building will not be approved! 😉

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