Nov 152011
 

Glazing and the Glass You Use for It-Part N

All forms of glazing need to comply with the relevant SANS.

Part N is the section on glazing in the National Building Regulations & Building Standards Act and is short and reasonably sweet.

Essentially you need to be sure that any material used for glazing in buildings is secure and durable and that it is fixed so that it:

  • safely sustains wind actions that one would normally expect wherever you live in South Africa (but not necessarily major hurricanes or tornadoes that might be experienced in other parts of the world),
  • does not allow water to penetrate the interior of the building, and
  • is obvious to anyone who approaches it (if it isn’t, people could walk right into the glass and be injured, particularly if it is completely transparent and not made of “safety glass”).

Of course it isn’t only glass that we use for glazing. There are also a number of plastic and polycarbonate materials, as well as organically-coated glass, which can be used.

When it comes to choosing the best type of glazing for the job, the essential aspect is to make sure that if someone (or an animal) does impact the glazing – or collide with it, they won’t be seriously hurt. Factors to take into account include:

  • the position of the glazing,
  • the number of people who are likely to be able to access the glazed door or window, and
  • the probably behaviour patterns of anyone (or anything) that is likely to get close to the glazed area.

And ultimately, as long as the glazing material is selected, fixed and marked in accordance with SABS 10400-N, all should be well and legal… and safe for all concerned.

NBR Changes that Relate to Glazing

The “new” National Building Regulations are a lot more specific in terms of glazing installations than they were previously. Not only is the maximum pane area and glass thickness specified, but so too are the different types of glass. These are:

  • monolithic annealed glass,
  • patterned annealed and wired glass,
  • laminated annealed safety glass,
  • toughened safety glass.

In addition to this, glass must also comply with the relevant SANS, as must the method of fitting the glass or alternative material used for glazing.

Just be aware that whether you are glazing doors, windows, shower cubicles, shop-fronts or anything else, glazing MUST comply with SANS 10400-N as well as other standards that relate to the manufacture of glazing materials.

Construction Standards of Glazing

The SABS also has a strategic policy that relates to glazing in buildings. The reason for this is to standardize glazing in buildings in terms of:

  • terminology (so that we all understand exactly what the regulations mean and relate to),
  • performance requirements,
  • various methods of calculation,
  • design and construction guidelines,
  • the classification and specification of materials (including dimensional properties).

To this end, the SABS has a sub-committee that specifically develops, maintains and co-ordinates standards in the field of glazing materials that are used in buildings. The committee’s responsibility is to:

  • develop national standards,
  • participate in the development of standards (getting votes, comment and so on),
  • develop and review the programme of work,
  • recommend what else needs to be done to ensure that the South African standards stay on track with international standards.

At the end of the day, the safety of users and installers is paramount.

Here is a drawing from the Standard that provides guidance

glazing

Examples of safety glazing requirements for exterior doors and windows.

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Lighting and Ventilation

  80 Responses to “Glazing”

Comments (78) Pingbacks (2)
  1. Hi

    Our window installer for our new house has finished his work. He sent the glazing cerrtificate to the builder who has left site. For some reason the glazer refuses to issue us a second one (or even a copy!).

    It seems I will need someone else to verify his work but lots of glazers aren’t willing to do so. Is there a way to compel the original glazer to issue or failing that, who would be able to verify other peoples work?

    Thanks
    Mark

    • I imagine that the person/company that did the glazing has a moral responsibility at very least to supply you with the certificate required. Any glazing company would be able to verify the materials etc but I think they would want to be paid to do this.

  2. Good day

    Please can you confirm whether a coated low e 6.38mm laminated safety glass can be glazed into a standard wooden frame with the the coated side facing inside or facing outside,are both options compliant? There is a sticker currently stating which side is the coated side but asking to confirm with the architect as to which way it must be fitted

    • Wayne I suggest you contact a reputable company like PG Glass and ask them, and/or contact the SABS.

    • Hi Wayne
      6.38 will normally fit in wooden frames if the rebate allows you to do so.
      The low-E should be on the inside and not on the outside.
      The glass suppliers normally indicate the non-coated side with a sticker.
      There are testers to check the coated side of the Low-E.

  3. Hi could someone please assist me, a client of ours requires stainless steel and glass balustrades for ther balconies,indoor staircase etc. Please could you let me know what the exact requirements are for the thickness of toughened glass, height etc?

    They are also looking at the stainless steel with horizontal cross bars option. How many cross bars are required and what is the maximum gap allowed between these bars?

    I have contacted balustrade specialists but have had very different answers. Any input would be greatly appreciated?

    • Nick the specifications for balustrades are detail in Part M of SANS 10400, Stairways. It is fairly comprehensively covered in the link given here. Glazing requirements are specified in Part N of SANS 10400, Glazing. In terms of balustrades, the latter states that “Safety glazing materials that comply with SANS 1263-1 shall be used where … f) glazing is used in any wall or balustrade to (or immediately adjacent to) a stairway, ramp, landing, pathway, patio, veranda or balcony;”
      “4.4.4 Glass in balustrades shall be toughened safety glass unless rigidly supported on all sides. Glazing material in balustrades is subject to the impact and line loads determined in accordance with the requirements of SANS 10160-2.”
      If you are supplying balustrades for clients, I suggest you buy both these parts of SANS 10400.

  4. I have recently updated my building plans to an As Built status and have had them approved. I then receive a letter informing me that I have to produce a glazing certificate and a soil certificate for a house which is 30 years old and has not had a single structural change or addition. Please advise

    • Andy my guess is that because the plans are “new” they consider that they must comply with certain things, including the new XA regulations. Which in turns makes me think that somebody is being stupid! I suggest you go into your local council and discuss the problem and insist that they waive this requirement. Clearly your glazing is not going to comply! Good luck, let us know what happens.

  5. In terms of the new Energy Requirements for Residential Buildings in South Africa, is their a regulation in the National Building Regs that says that if you design a Residential Building your Glazing section, ie Windows and Glass doors where the total area of glass must not exceed 15% of the nett floor area of the building, if not it does not meet the Energy code?

    Regards
    Peter

    • Hi Peter, Correct, it is the new SANS 10400X & XA. We have given a brief rundown to help explain the situation on this page here: energy-usage Since 2011 when the new regulation was set, architects have been attending courses to get to understand the new regulations, most by now will have applications that do the calculations for them as well. If there is a specific problem that you have then you should get your local building inspector to give a ruling so that plans are not rejected when you submit them.

  6. My house has cottage pane glass windows. The putty was falling out and I asked the local glazing company to fix. They elected not to use putty again but used wooden strips, the job took 4 instead of 2 weeks, I had contacted them as the work was done vey poorly, the owner apologised and sent other workers to fix. The work looks much better, but I now find that in most places they did not seal the windows and when sprinkling the garden the water enters the house. Is there a standard that has to be adhered to regarding sealing the windows?

    • Rudi that’s just plain bad workmanship. They should have used a silicone or some other kind of sealer in the gaps before fixing the strips. Tell them to come back and redo it – and give them seven days to do so. Put it in writing. Say otherwise they must refund your money. While you probably don’t want to get nasty, explain that you can’t continue to pay for shoddy workmanship – you could threaten legal action or going to Hellopeter if they don’t oblige.
      In terms of standards, SABS standards generally cover products rather than procedure when it comes to minor things like this. There may though be a standard. Call an SABS library and ask them to check for you. It is not part of the NBR.

  7. Subject:
    Glass Panel breakage

    Message:
    As part of an extension to the first floor of our house we had a new oak staircase fitted and this included six glass infill panels. The work was carried out by Hallmark Glass and Glazing Ltd of 49 Potters Field, Harlow CM17 9BZ in July 2011 (Tel No. 01279 410304). Our problem is that this morning
    the long glass panel going up the stairs exploded and shattered, causing considerable shock, from which I have hardly recovered. I got in touch with Hallmark and they maintain that the work is outside
    their warranty period and there is nothing they can do. My point to them is that glass doesn’t just break unless there is a fitting problem. I would be pleased to know from you where I stand on this and what action I can take against Hallmark. You advice would be greatly appreciated.
    John Farrow (Tel: 01582 769975). We live in Hertfordshire.

    • Hi John, We would love to help you but I think we are a bit out of your area here in South Africa. I am sorry to hear of your dilemma and hope you find a solution.

  8. Hi

    We are about to open a retail store with street front access in Cape Town CBD. We have just been told that our glazing may be illegal – it’s standard 6mm non-safety glass, only one or two of the 6 or so 3m x 2m panes is even laminated.

    Are there any legal stipulations for glazing in retail space? And if so, would our store be in contravention of these rules?

    • Steve the National Building Regulations apply to all glazing. There are tables in SANS 10400 Part N, Glazing that state nominal pane thickness in relation to maximum pane area and type of glass.
      If it is vertical glass that is supported by a frame on all sides in an external wall of the building, where the height measured from the ground to the top of such wall does not exceed 10 m, then it has to be monolithic annealed glass 10 mm thick; or toughened safety glass that is 8 mm thick.
      The drawing on this page is taken from the regs and shows when safety glass is not required.
      If someone falls through your glass – or walks into it and is injured – you could be sued.

      • I agree in part. But if a smash and grab safety film was applied, wouldnt this conform.

        • Gary I don’t think so. It is not even mentioned in the regulations! My understanding is that it could be used in addition to the correct type of glass as an added safety factor.

  9. I’ve been a glazer and sand blaster for about 15 years now and aluminium manufacturer for 10year but I don’t have a certificate. I now want to open my own company but don’t have a certificate.

    How and where can I get the certificates necessary to be qualified as a glass glazer and aluminium manufacturer.

    • Hi Thando,
      Agrément SA, part of the Department of Public Works, is the body that issues certificates for construction materials and manufacturers. You can find all the info you need on their website here: Agrément SA

  10. Hi there

    I just want to understand the regulations for when Low E glazing becomes a necessity when building a house. Is it not the owners decision on whether they want normal glass or Low E glass. Can the municipality insist on new buildings having Low E glazing and if so when did this regulation come into being and where can I read up on it?

    Thanx, Mervin

    • Hi Mervin,
      The new regulation that you are referring to is a new part and was added to SANS 10400 in 2011, Part X deals with environmental sustainability, and Part XA deals with energy usage in buildings. You do not have to use Low E glazing, BUT your building must conform to the new Energy Usage regulations. You can read more here: energy-usage If you need any assistance with your calculations you can contact John Crook at jdctri@gmail.com and 073 144 2600 or visit his website http://www.sansrvalues.co.za/

  11. Good day.
    I have made and disigned a aluminium stackable door system for patios and lapas.
    It is an aluminim frame glazzed with 2mm Plexiglass,acrylic.What are the regulations if any for the use of arylics for glazzing.I have fitted it in my patio and have recieved alot of intrest in it.If I would start to manufacture and fit what regulations do I need to adhere to.
    Please could you help or send me in right direction to move forward.

    Regards Terry

    • Hi Terry,
      You will have to contact the SABS and have your product approved by them. As far as I know they will refer you to Agrement SA (www.agrement.co.za) who will need samples to test and then issue you with a certificate before you can take the product to market. The SABS offices contact numbers are on this page: http://sans10400.co.za/sabs-contact/

  12. Help!
    I built my home in july 2002. I have French cottage pane doors which
    open onto a patio. At the time i got a reputable glazing company to do
    the entire glazing job at my home. This they did and i paid them
    accordingly. I have now been asked by the municipality to supply a
    glazing certificate, which i honestly dont recall receiving. What
    where the glazing regulations in place in 2002? I believe you now
    require safety glass which may not have been installed originally. Can
    you advise what i should do as it seems quite an expensive excercise
    to have to put in safety glass when i have been living here without
    incident for 11 years

    • Howard, first of all there is nothing in the current (NEW) SANS 10400, Part N Glazing that mentions any type of certificate. The new Part A General principles and Requirements which waas published in 2010 has a form that the appointed competent person is required to fill in. The section on glazing asks these questions, to which they reply Yes or No:
      “The type and fixing of glazing is in accordance with
      SANS 10400-B [which is Structural Design]
      the detail requirements of SANS 10400-N
      The selection of the glazing is in accordance with the detailed requirements of SANS 10400-N”
      NOTHING about certificates. But there may be something in the municipal by-laws that requires a certificate. If they didn’t ask for it then, I agree with you that they can’t ask for it retrospectively. Presumably they gave you an occupancy certificate? In which case they approved the building. Fullstop.
      And yes the new regs do require safety glass in cottage pane doors, as you will see from the drawing on this page.
      The new Building Regulations came into effect in 2008 (progressively until last year – as I say above, Glazing was only published in 2010). Until then all the SANS (previously published as South African National Standard SABS 0400-1990) were regarded as the applicable Code of Practice for compliance with the NBR. I have given you the link to download these. NB They are available free from this website and from the SABS. You are required to purchase the new regs.
      You will see in the old document that safety glass is a requirement in certain instances, see pages 96-99. Doors, specifically are referred to on page 96. “Any pane of glass installed in any door shall, where not made of safety glass, be not more than 1 m2 in area and shall have a nominal thickness of not less than 6 mm”. I doubt that cottage panes would be more than 1 m2 – no idea what thickness would have been used. But for the municipality to make any demands more than a decade after completion is ludicrous.

      • My own experience is different; unfortunately some officials do not care whether there are historic issues and whether the building does or does not conform to these. A friend of mine recently sold her house in Howick and the Municipality refused to issue her with what she needed to finalize the sale until she had a glaziers report. Luckily her home complied and no additional cost had to be incurred other than the report itself.

        Unfortunately their standard answer is “you are welcome to take us to court”, but this is not a reality when a sale is reliant on their approval.

        • My experience with Howick was the pits 🙁
          When my mom sold her house in Howick a couple of years ago the municipality planning office did not have plans on file any more as they had lost them when the municipality offices moved. My mother had to have the plans redone from scratch at her own expense. Lack of caring by public servants for the people who pay their salaries is inexcusable.

  13. Hi everyone.

    I am looking for the regulation that defines whether a western facing window needs to be sandblasted or covered. I have a double storey house with a large western facing window above the entrance but it is covered by the entrance roof. Does it need to be sand blasted???

    Thanks in advance!

    • The regulations are not this definitive. If someone is trying to persuade you that the regs say it must be sandblasted … ignore… if your wife wants you to have it sandblasted … you might want to do it. But it isn’t law. Though do realize that if it is a bathroom window it should be opaque … your wife will appreciate this!

  14. From what I understand, windowglass cannot exceed 15% of netto area,
    we want to put in sliding doors, if exceeding the 15% can one use
    E-glass, or does the 15% includes e-glass and normal glass for area

    • Valmarie, The new Part X – Environmental sustainability – and XA – Energy usage in buildings – deals with fenestration [defined as any glazed opening in a building envelope, including windows, doors and skylights].
      This Part of SANS 10400 has a section on fenestration that states:
      1. Buildings with up to 15 % fenestration area to nett floor area per storey comply with the minimum energy performance requirements.
      2. Buildings with a fenestration area to nett floor area per storey that exceeds 15 % shall comply with the requirements for fenestration in accordance with SANS 204.
      So the percentage relates to all forms of fenestration, including both doors and windows. And it doesn’t say you CAN’T have more than 15% – just that if you do you must do it correctly in accordance with the Standard (SANS 204).
      SANS 204 doesn’t only look at the glass used, it also considered the orientation of the house and other factors, and is rather technical.
      Amongst other things, there is a table that gives the “worst-case whole glazing element performance values” for different types of glass in relation to the type of framing e.g. aluminum and steel vs timber, PVCu, aluminum “thermal break” framing.
      The Standard states: “With glazing, this standard requires that total U-values and SHGCs shall be assessed for the combined effect of the glass and frame. The measurement of these total U-values and SHGCs are specified in the guidelines of the National Fenestration Rating Council (NFRC).
      The method used in this standard is based on the system performance of glazing being assessed in accordance with NFRC 100 conditions.”
      You can get the necessary info from manufacturers and suppliers, but it is essential that the info (particularly the U- and SHGC-values) are for both the glass and frame combined.
      Be advised that your best approach will be to get a competent person to help you.

  15. I’m looking for the regulations that govern glass and the installation
    of glass (e.g., shower doors must open outwards, patio doors must have
    toughened glass etc…).

    Where would I find these regulations?

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