Energy Usage & Sustainability (SANS 10400X & XA)

Environmental Sustainability &
Energy Usage in Buildings-Part X & XA

energy usage
Glazing and lighting are two vital factors when it comes to energy usage.

In 2011, in an endeavour to make our buildings more sustainable, and to decrease energy usage in South Africa, a new part was added to SANS 10400, The application of the National Building Regulations. Part X deals with environmental sustainability, and Part XA deals with energy usage in buildings.

In many ways these new regulations have turned the building industry upside down, but not in a bad way. However for the average man-in-the-street it has become a puzzle of note. Every week we get people writing into this web site asking for advice and information about the “new energy laws” and how they affect their building and renovations.

On the down side, it seems that new regulations have opened up a can of worms that has less-than-knowledgable people (and some scamsters) flippantly quoting “the new green laws” in an effort to force people to spend more money than they need to on energy-efficient materials, appliances and the like. While there is no doubt that we need to “go green” and get our act together (pun intended) in terms of energy efficient building, it is also important to know the difference between what we should do, and what we must do to comply with the National Building Regulations and other national standards.


What the National Building Regulations and
Building Standards Act Says

While the Act was originally passed in 1977 (officially it’s Act 103 of 1977), a number of amendments have been added to it over time. In 2011, Rob Davies, the Minister of Trade and Industry added the sections that relate to environmental sustainability and to energy usage in buildings.

The motivation for this amendment is to reduce greenhouse gases caused by buildings and extensions to buildings. These relate to a number of specific occupancies that are defined in Part A of SANS 10400, namely:

  • A1 – Entertainment and public assembly Occupancy where persons gather to eat, drink, dance or participate in other recreation.
  • A2 – Theatrical and indoor sport Occupancy where persons gather for the viewing of theatrical, operatic, orchestral, choral, cinematographical or sport performances.
  • A3 – Places of instruction Occupancy where school children, students or other persons assemble for the purpose of tuition or learning.
  • A4 – Worship  Occupancy where persons assemble for the purpose of worshipping.
  • C1 – Exhibition hall Occupancy where goods are displayed primarily for viewing by the public.
  • C2 – Museum Occupancy comprising a museum, art gallery or library.
  • E1 – Place of detention Occupancy where people are detained for punitive or corrective reasons or because of their mental condition.
  • E2 – Hospital Occupancy where people are cared for or treated because of physical or mental disabilities and where they are generally bedridden.
  • E4 – Health care Occupancy which is a common place of long term or transient living for a number of unrelated persons consisting of a single unit on its own site who, due to varying degrees of incapacity, are provided with personal care services or are undergoing medical treatment.
  • F1 – Large shop Occupancy where merchandise is displayed and offered for sale to the public and the floor area exceeds 250 m2.
  • F2 – Small shop Occupancy where merchandise is displayed and offered for sale to the public and the floor area does not exceed 250 m2.
  • F3 – Wholesalers’ store Occupancy where goods are displayed and stored and where only a limited selected group of persons is present at any one time.
  • G1 – Offices Occupancy comprising offices, banks, consulting rooms and other similar usage.
  • H1 – Hotel Occupancy where persons rent furnished rooms, not being dwelling units.
  • H2 – Dormitory Occupancy where groups of people are accommodated in one room.
  • H3 – Domestic residence Occupancy consisting of two or more dwelling units on a single site.
  • H4 – Dwelling house Occupancy consisting of a dwelling unit on its own site, including a garage and other domestic outbuildings, if any.
  • H5 – Hospitality Occupancy where unrelated persons rent furnished rooms on a transient basis within a dwelling house or domestic residence with sleeping accommodation for not more than 16 persons within a dwelling unit.

But they specifically EXCLUDE garage and storage areas contained within these specified occupancies, as well as a number of other buildings that are used for commercial, industrial and buildings used exclusively for a variety of storage uses.

The law (because this is part of the Act – not SANS 10400) states that these “occupancies” (types of buildings) must be:

  • capable of using energy efficiently while fulfilling user-needs in relation to various things including thermal comfort, lighting and hot water; OR
  • have a “building envelope and services” that facilitate the efficient use of energy that is appropriate to the function and use of the building as well as its geographical location and its internal environment.

So it is not a one solution fits all situation. For instance, what works for a house in Durban may not make the same structure energy efficient in Cape Town! In addition, the legislation excludes the “equipment and plant” required for conducting business – if the building is used for business.

Hot Water Heating Requirements

XA2 requires that at least a half – “50% (volume fraction) of the annual average hot water heating requirement shall be provided by means other than electrical resistance heating including but not limited to solar heating, heat pumps, heat recovery from other systems or processes and renewable combustible fuel”.

So you can use a conventional geyser IF you meet the 50% requirement. And if you are renovating, you certainly don’t have to toss all your existing water equipment and go solar – even though there is absolutely no doubt that it’s the way to go.

What is Required

The orientation, shading, services and building envelope must be designed according to SANS 10400 Part XA. Alternatively the rational design of the building must be done by a competent person who “demonstrates that the energy usage of such building is equivalent to or better than that which would have been achieved by compliance with the requirements of SANS XA, or has a theoretical energy usage performance, determined using certified thermal calculation software, less than or equal to that of a reference building in accordance with SANS 10400 Part XA”.

If you’re looking to change jobs, becoming a person competent to specify these requirements is one way to go! It is something that is not easy for someone who hasn’t got the relevant training to get their head around.

What 10400 XA Says

As with all national standards, 10400 XA has a number of definitions, some of which are in the glossary that is part of the Act.

A few of the important definitions that relate to this particular part of the standard are:

  • Building envelope Elements of a building that separate a habitable room from the exterior of a building or a garage or storage area 
  • Competent person Person who is qualified by virtue of his education, training, experience and contextual knowledge to make a determination regarding the performance of a building or part thereof in relation to a functional regulation or to undertake such duties as may be assigned to him in terms of the National Building Regulations
  • Fenestration Any glazed opening in a building envelope, including windows, doors and skylights
  • Fenestration area Area that includes glazing and framing elements that are fixed or movable, and opaque, translucent or transparent

Requirements of 10400 XA

The requirements of this new national standard cover:

  1. Hot water supply
  2. Energy usage and building envelope
  3. Design assumptions
  4. Building envelope requirements

The standard also defines the different climatic zones of South Africa.Climate-zones-XA1

To be a little more specific, the main centres for each zone are:

  • Zone 1 – Johannesburg and Bloemfontein
  • Zone 2 – Pretoria and Polokwane
  • Zone 3 – Makhado and Nelspruit
  • Zone 4 – Cape Town and Port Elizabeth
  • Zone 5 – Durban, Richards Bay and East London
  • Zone 6 – Kimberley and Upington

Building Envelope Requirements

This is probably the most vital part of the new regulation, and it addresses orientation, floors, external walls, fenestration, and roof assemblies – but not in a lot of detail.


If any type of underfloor heating system is used in a home, this must be insulated under the concrete slab with insulation that has a minimum R-value of at least 1,0. The R-value is the thermal resistance (square metre K/W) of a component. According to the Standard, it is “the inverse of the time rate of heat flow through a body from one of its bounding surfaces to the other surface for a unit temperature difference between the two surfaces, under steady state conditions, per unit area”.

Roof Assemblies

Any roof assembly must achieve a minimum R-value for the direction of heat flow. This is specified in several tables in the regulations.

 Minimum total R-values of roof assembliesenergy usage

Roofs with metal sheeting affixed to purlins, rafters or battens made of metal are required to have a thermal break that consists of a material with an R-value that is not less than 0,2, and which is installed between the sheeting and the support. In addition, roofing assemblies that utilize metal sheeting must achieve a minimum total R-value that meets the requirements shown in the table above. Insulation must also be installed with an R-value that meets the specified in the table below.

Metal sheeting roof assembliesenergy usage

Clay tiles used for roofing must achieve a minimum R-value as in the first table above. Insulation should be in accordance with the specifications shown below.

energy usage

The other standard that you need to know about is
SANS 204 (2011): Energy efficiency in buildings.
(click for preview from SABS Store)


Why National Building Regulations


About Penny

Penny Swift is a highly regarded journalist and author of books relating to homes and construction.

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  1. My plan was approved in Sep 2011. I have completed the building and still awaiting for the Certificate of Occupancy. I have added a balcony in one of the rooms in the development.I have informed my architect about this structure. Do I have to submit a new plan or just submit the added structure only to the local municipality?

  2. My neighbours roof design was a boxed roof. He had opted for a more simpler roof ( tuscany ) Does he have to amend his roof plans?

  3. Hi Richard,
    It depends if the roof design is changing, if it is, then an amendment/rider to the plan will be needed. The other important factor is the material used. If the boxed roof has metal sheeting as a covering and he is changing to a tuscany, which implies clay tiles, then yes amended/rider plans will have to be submitted. The difference in the structural design for metal sheets and clay tiles is completely different and must be shown on the plans. There is also some quite useful info in our book “Owner Building in SA” and you might like to get a copy 🙂

  4. Hi Richard,
    You will only have to submit a amendment/rider plan to council with the addition. Your architect will know what is needed and should supply you with the correct documents.

  5. I have completed building a house with plans approved in Sep 2011,I am waiting for the certificate of occupation from the local authorities.
    I have added a balcony on the new development. Should the whole plan be re-drawn or should my architect draw up the added part only?
    What is the impact of the new energy regulations?

  6. Richard your architect – presumably the competent person you appointed – should be able to answer both your questions. A rider plan should be perfectly adequate. And since the new energy regulations were published in August 2011, these should have been complied with. If they weren’t it was the local authority’s responsibility to call for amendments.

  7. Hi

    My plans for an extension to my residential dwelling have been submitted to the local authority for approval. My architect has now informed me that we require a SANS specialist to sign-off on the energy efficiency of the house at an additional cost of R12,000!!! Is it compulsory for a specialist to sign-off or are there specified regulations that the architect coulf follow to comply with the energy SANS?

    Thank you.

  8. Nancy it is up to the competent person appointed for the job (by the owner) to determine whether additional competent persons are needed to sign off parts of a job. There is a form that the competent person fills in prior to submission of plans. This details when an additional competent person may be required, specifically:
    1. a civil or structural engineer for structural design; or a person who is experienced with dolomite land if applicable.
    2. a civil engineer or geotechnical expert for foundations.
    3. a civil engineer where floor slabs are supported on the ground.
    Further, before plans can be approved, “approved competent person appointments” must be made. This forms includes the possible need for a competent person in the field of built environment (e.g. an architect) to deal with the rational design and rational assessment of flat roofs and related gutters; a civil engineer to design and control stormwater disposal; a mechanical engineer for the design of ventilation systems (Part O); it also relates to sanitation and fire installations. BUT these experts are not always required by any means.
    If your architect is the appointed competent person and he/she is saying “a SANS specialist” is required to “sign off” energy efficiency compliance, it seems to me that this person simply does not have an understanding of the new regulations pertaining to energy efficiency. There are many workshops being held all over the country for architects – because they are all basically in the same boat. If your architect needed some sort of energy efficiency specialist, that person should be listed on the official form.
    Frankly I would say that if your architect did not inform you initially that he/she was not sufficiently knowledgable in terms of the new SANS (specifically SANS 10400 X & XA and SANS 204: Energy efficiency in buildings) and would need assistance that you would have to pay for, then it is up to the architect to cover this additional bill. It’s a bit like employing a contractor to build your home – and then he puts in an additional bill for the roof trusses or for steelwork that is noted on the plans).
    We can give you the name of an architect who specializes in energy efficiency if you wish. But our feeling is that it is the responsibility of your appointed competent person to sort out any issues.

  9. In the R value tables for the different climatic zones you refer to a unit m2.K/W. What is that? Shouldn’t it be m2 / kW?

  10. Marcel we have presented info from the SANS – this is not something we compiled. If you have a query please contact the SABS. If you get useful info it would be good if you would let us know. THANKS!

  11. Where can we get a copy of the tabels as refered to in the Sans Regs?

  12. Abodezign, We have some tables on this site – otherwise you need to access the relevant South African National Standard (SANS) from the SABS. If you don’t want to buy the SANS, you can visit an SABS library and have a look at it there.

  13. kervin govender

    Hi there,
    We want to convert our patio into a sunroom. According to our architect we have to the fenestration calculations . These calcs amount to us only being able to install a q2.4×1.2 glass door and a 1×1 window. This defeats the purpose oof doing the sunroom. Please help ifon how we can do this without contravening any regulations.
    Thank you, Kervin Govender

  14. Subject:
    Climatic Maps for Rv Values

    Dear Sir / Madam,
    Could you please assist in aforementioned climatic map for future construction project, want to go completely sustainable etc

  15. Subject:
    SANS 10400-XA (DSS3)

    The municipality is asking for the “Sans 10400” for approval of building plans.

    Do they want the full document (19 pages) ?

  16. Subject:
    House Doors (External)
    I would like to know the regulations on how many doors there should be leading into the house, and whether glass sliding doors are fine?

  17. Joe there is no regulation that specifies how many doors should lead into a house. Generally glass sliding doors are acceptable, provided the glass used meets the specifications.

  18. Hi Joe,
    I think that this will come under the new SANS 10400 X & XA regulations and you can see more on this page here: “Energy usage in buildings” But it seems to be a regulation that is interpreted differently be each Local Council at the moment so I suggest that you contact them and ask their opinion.

  19. Hi Menno,
    I am not sure what you mean or what it is that they want. The SANS 10400 are the set of Standards that all buildings and building processes have to adhere to. You do not have to submit these when you want to get your plans approved. It is your plans that have to comply with the SANS 10400. At the back of the SANS 10400 Part-A there are a few example forms that act as guidance for local authorities that have to be completed when plans are submitted. They should have the forms that are needed for your project. You certainly do not have to fill in forms that are not relevant to your job.

  20. Hi Anton,
    The map of South Africa and the various zones are here on this page: “Energy usage in Buildings”

  21. Can you use Window tint on existing glazing to comply with new regulations? If so, how would I be able to work out which tint to use?

  22. There are window films which meet the same specs as tinted glass, why can they not be used in place of the tinted glass? The costs are far less and it is far easier to have installed. Please can you give me a reason why it cannot be used?

  23. Jeff there is no reason why they cannot be used instead of tinted glass. However the glass itself must meet the specifications of SANS 10400, Part N: Glazing. This is specifically to ensure that the glass will be safe and will withstand human impact if this is a possibility.

  24. The U-value of a construction consisting of several layers can be expressed as

    U = 1 / ∑ R


    R = “R-value” – the resistance to heat flow in each layer (m2.K/W)

    Hence the units for the U-Value is W/m2K.

    see for more information

  25. Good Day

    I am looking for the NBR in respect of thermal insulation applied to hot water piping. Is there anything stipulated in terms of thickness, heat loss and type of insulation that should be used….???

  26. H Derek, The new building regulations SANS 10400XA does address thermal insulation but does not specify thicknesses etc. This would be controlled by the Agrément Board when they approve a company’s thermal product for market. One of the best in SA is Isotherm, I suggest you contact them as they will have specifics on hand for you. Click here:

  27. Kervin if I were you I would get advise from other architects because there seems to be considerable misinterpretation of the new fenestration calculations. I will also see what I can find out, because this is a question that a lot of people are currently asking.

  28. Subject:
    Hot water supply

    Hi there,

    I need some advice please. We bought a property in Struisbaai in 2006.
    In 2008 we employed an architect to draw up our plans, with the understanding that we would not immediately walk the plans. However at the end of 2012/start of 2013 we then advised that we are now ready. He then advised us of the new energy efficiency regulation which we then paid for. We asked him in Feb 2013 to walk the plans but for some reason this did not happen. We are now at the stage where the plans has finally been submitted, but the Municipality is advising that the warm water layout has not been done. Initially our architect advised that he did do this, but now he is saying he does not understand what they are asking for. We are now stuck between a rock and a hard place
    because we do not understand what is missing from the plan. The architect claims he has included everything that needs to be on it – however, the municipality will not approve then plans because they
    claim the warm water layout was not done.
    Please could you advise if you have any ideas on how we should proceed. We have already paid the plan fees.
    Kind regards,
    Nazley de Vos

  29. Subject:
    Regulations for Windows.
    To whom this may concern,
    I have a comment from fire saying “Total area of windows in east elevation of first floor my not exceed 5 square meters” Can you please explain this to me or tel me where I can find this in the building regulations.

  30. Hi Nazley, have a look at this page: paja-law-protect-rights. There are two forms that you can download and submit to the council. If your architect has done his job properly then the council must do theirs and supply you with very good reasons why they will not approve your plans. You can also put your architect to terms as there is problem with the professionals interpretation of the new XA regulations and the client must not be made to suffer because of this.

  31. This is part of the new XA and Energy Regs.

  32. Hi Penny

    I have plans in council (they were submitted in December 2013) and have just been asked to supply Electrical Calculations for XA – ie an electrical layout plus calculations. Do you know when exactly this become a requirement? If I submitted before it became a requirement does that mean it doesn’t apply to me – i have complied with all the other XA requirements that we knew about before we submitted? Who is the competent person here – the architect? Thanks so much!

  33. Bridget there is nothing in XA that even mentions electrical calculations – unless an amendment has been posted that I am not aware of. I suggest that you contact council and ask them to refer you to the specific section of XA that covers this requirement. I’d be very interested to know how they respond. As far as the competent person is concerned, I assume it would need to be a qualified and registered electrician or an electrical engineer. If your primary competent person is an architect that person could organize the competent person to sign whatever documentation is required. I have also looked at SANS 204 (2011) Energy efficiency in buildings and there is nothing about electrical calculations there either. Could it be energy calculations?

  34. Hi Penny,

    Who is supposed to police the correct implementation of SANS 204? We have found some municipalities still passes plans without consideration for 204.


  35. Hello

    I am planning to build a dome house. I am not familiar with the South African regulations and want to ask you which ones relate to a dome house. Energy efficiency is one advantage that is easy to obtain with the dome house. I am planning to use a steel structure for the basic structure (i.e. skeleton) and cover that with concrete. I have built many similar strutures in the US but I need to know which South African regulations relate to this type of structure.I plan to use it for permanent living accomodation.
    Please tell me which building regulations apply to this type of construction.

    Thank you

  36. Hi
    Where can i get training to become competent in order to sign off SANS 10400X and XA forms for council?

  37. You need to be qualified as a competent person Nhin. The link I have given you provides more information.

  38. Peter, All the National Building Regulations apply to a dome house, however you will also eed an “agrément certificate that confirms fitness-for-purpose of a non-standardized product, material or component or the acceptability of the related non-standardized design and the conditions pertaining thereto (or both) issued by the Board of Agrément South Africa”. These certificates are covered in Part A of SANS 10400, General Principles and Requirements

  39. Good point Murray. The trouble is that the municipalities follow the National Building Regulations, but not the unending lists of other SANS that come into play. Just about every section of SANS 10400 cross references at least one A4 page of other standards. I suppose this is left up to the so-called “competent” people who are drawing up the plans and making the specifications.
    Clearly you have some link to an energy efficient industry – what is it that you see them ignoring?

  40. Hi Penny,

    Thanks for the reply. I find most of the bigger metro’s hve implemented SANS 204, however it is the smaller municipalities that are behind in implementation, specifically on regulation XA2, (Hot water) which is the part I am interrested in. I am in the solar water heating industry and most of our agents throughout the country has experienced an uptick in sales because of the new regulation. A few guys however are losing out as a result of it not being implemented in their areas, and of course the bigger reality is that houses gets passed for building that are not contributing to a cleaner, greener environment.


  41. Regulation XA2 discriminate against other renewable enegy resources such as photovoltaic solutions. Simpler more cost effective virtually maintenance free solutions are available.Unfortunately municipalities interperate the generation and heating of water by Photovoltaic as electric resistive heating. I have lots of data on hand to prove that this is safer , economical , on par with thermal solar ,simple installation no plumbing piping , no pumps suitable in any winter conditions ,no freezing.

    How do one get these regulations ammended.


  42. Meinhard, You cannot simply get the regulations amended. You could though contact the SABS in Pretoria and ask who was the main person involved with this particular part of the NBR and approach that person. I assume any objection like this would have to go to the original committee that dew up the regs.

  43. Subject:
    Body corporate building regulations

    Dear Sirs,

    I am trying to find out what act or law regulates glass panes in body corporates, is there any way you could assist me?
    I also want to know if changes to legislation apply retrospectively?
    Thank you for your assistance.

    Richard Baruch

  44. Kuveshen Chetty

    Domestic Residence Building


    I’m building a home in a cluster development, and is the first time I’m doing so. There are a number of items which are coming to my attention that I haven’t been fully made aware of or think my Builder
    is taking a chance with.
    I’ve been requested to pay for Thermal insulation in the roof, which I thought is something that should be building regulation and is at the expense of the Builder rather than me. Likewise, my Geysers are on a slab open, which I would think requires at the very least a thermal blanket. I am going to install
    heat pumps at a later stage, but with this being open, I think the energy efficiency is important, and don’t think it would pass building regulation. In terms of glazing, I have been informed that there would
    be standard glazing, but someone has indicated that the building standard is 6.38mm laminate for single glazed windows. All my light fittings are to be LED in terms of energy efficiency, and I don’t have
    underfloor heating, which I was also informed doesn’t require any insulation unless I do.
    Please assist.


  45. Kuveshen, There are two issues here, the building regulations and your contract. While your house must be built according to NBR guidelines, all specifications including things like insulation, should be in your contract – or on the plans which should then be cross-reference in your contract. SO, for example, if standard glazing is specified on the plan, that’s what you will get. I am presuming you didn’t have the plans drawn up. If this is the case you need to find out who drew them and get clarity from that person. In terms of the building regulations the person drawing the plans must be a competent person as defined by law.

  46. Richard there is only one set of building regulations and it applies to all buildings. A body corporate may impose additional regulations of its own. Generally the NBR changes are not applied retrospectively unless there is a major alteration.

  47. hi,

    We have recently bought a house and are wanting to alterations on the property, namely, building double garage and extending kitchen area. We seem to be running into endless problems – the previous owners had alterations on the property which were not on plan (prior to the regulations); the property has soakpits and the competent person drawing the plans says that the whole property has to comply with the regulations and new plans are being drafted and the soakpits have to be dug up and investigated.

    My question – if we are only making alterations (i.e. building a garage) surely only that alteration has to comply with the new regulations and a new owner surely cannot be held responsible for the previous plans/alterations not being in accordance with the regulations at present (i.e. not retrospective)

  48. Dan, A new owner can be held responsible for irregularities that occurred prior to purchase of the property. You can though have “as built” plans drawn up and submit these to the local authority. It will be up to them to call for any changes to be made in terms of the new regulations.
    The whole property does NOT have to comply with the new regulations. You say prior to the regulations? Which regulations? There have always been regulations of some sort or another. The Building Regulations and Standards Act, along with accompanying SABS “deemed-to-satisfy rules” – originally referred to as a Code of Practice for The application of the National Building Regulations – came into effect in 1977. Prior to that building was done according to the bylaws of the various local authorities (municipalities).
    When you talk about “soakpits” what do you mean? In rural areas septic tanks and soakaways were very common until recently. Now conservancy tanks are more usual for properties that are not on mains sewerage. If you have cesspits – those were and still are illegal and would need to be dug up or filled in and replaced.
    If the house was originally built legally, changes do not have to be retrospective.
    Part A of SANS 10400 states:
    “Where an application is made to make an alteration or addition to any building, approval for the erection of which was granted before the date of commencement of the Act ––
    (a) such alteration shall comply with the requirements of the Act, but consequent changes to any other part of the building which would be necessary in order to make such other part comply with the requirements of the Act shall not be required unless in the opinion of the local authority such consequent changes are necessary to ensure the health or safety of persons using the building in the altered form;”
    Your sewerage system may well be perceived by the local authority to be inadequate. But let them inspect it first before your “competent person” makes you dig things up!

  49. Hi Penny

    I need some advice please with regards to the roof insulation. My new home is currently being built. On my plan under Roof Assemblies, the R-Value was 0.4. The statement says that 135mm Aerolite Roof insulate is required to get an R-value of 3.78 (minimum is 3.2) to comply with SANS 204. On my building contract no insulation is indicated under Roof section or anywhere else in the contract. Is it mandatory to have roof insulation and if yes, who is now responsible? Neither the building contractor nor their architect indicated or advised on this aspect as part of the NBR. It was only after I saw another contractor installing the aerolite into a house that he was building that prompted me to look into this aspect.


  50. Espri, If insulation is indicated on the plan, then it MUST be included because those are the approved plans – they would not have been approved if this was not specified. Presumably the contractor quoted in accordance with the plans? Further, if the roof insulation does not comply with SANS 204 Energy efficiency in buildings, 2011 then the building will not be legal. So yes it is mandatory and it is the contractor’s responsibility to ensure that it is included. Note that SANS 204 is not part of the National Building Regulations SANS 10400, but is, like many other SANS, a requirement of building. Roof insulation falls under 4.3.6 Roof assemblies General A roof assembly shall achieve the minimum total R-value specified in table 8 for the direction of heat flow. Thermal insulation Insulation shall comply with minimum required R-values and be installed so that it …. THIS NEXT PART IS QUITE LENGTHY
    More specifics are given in this table:
    Table 10 —— Typical data and deemed-to-satisfy thicknesses of generic insulation products (this includes Aerolite-type products)

    But all this is already spelt out on your plan… and this is what the builder needs to ensure he complies with.

  51. neil alberts

    Hi Penny,

    I have bought a house recently but it was found that the original plans do not comply as to what is currently on the proprty. The owners have done alterations to the property without plan and approval. None the less new plans have been submitted and pproved by council but now they require the certain of the windows be removed and replaced with smaller windows to comply with the regulation.

    Is there an alternative to removing the windows to save costs? Perhaps a film type material to cover the windows?

  52. Neil, I need to find out more about the new energy regs (2011) because I have not convinced the people dealing with them in the various municipalities are getting it right. For instance people are being told they must convert to solar heating which is only one of the options in the regs.
    In terms of windows, XA says, “Windows facing east and west should be limited in number and confined to the minimum required for daylight and ventilation.” I am not sure how this is calculated – SANS 204 has some very complicated fenestration calculations.
    XA also says “Living spaces should be arranged so that the rooms where people spend most of their hours are located on the northern side of the unit.” So what if you live in Upington? You must live baking in the sun? Although SANS 204 does have different glazing requirements for different areas.
    Fenestration is the key issue from what I can tell – fenestration = “any glazed opening in a building envelope, including windows, doors and skylights” & fenestration area = “area that includes glazing and framing elements that are fixed or movable, and opaque, translucent or transparent” – which is all about windows.
    (Still with XA)
    4.4.4 Fenestration Buildings with up to 15 % fenestration area to nett floor area per storey comply with the minimum energy performance requirements. 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.
    SANS 204 also deals with energy in buildings:
    “Fenestration refers to the arrangement, proportioning, and design of windows and doors in a building. The energy efficiency of the building envelope is greatly impacted by the fenestration systems. Windows strongly influence the use of the building and the productivity and comfort of its occupants.”
    There is absolutely no doubt that glazing and fenestration go hand-in-hand – and I am convinced that it is not simply a matter of saying windows must be smaller – rather that the glazing type should be compliant depending on the size of the window.
    Then there is the issue that the new regs are not intended to be retrospective. Even though your plans have only now been done, these would be “as built” and therefore should be compliant with whatever the regs were at the time.
    I’m going to do some more homework and will let you know.

  53. Hi Penny,

    Do you know if there are there any regulations or laws requiring plan submission for the installation of solar PV panels on a flat concrete roof? the panels lie flat on the roof and including the mounting structure they stick up 25cm higher than the flat concrete roof.


  54. Stu as far as I know you do not require plans for solar panels, but the manufacture and installation would need to meet SABS specs. The SABS should be able to advise further.

  55. hi Penny,

    I spoke to them and got the following feedback:

    All PV roof top installations: No building plans are required to be submitted provided the panel(s) in its installed position does not project more than 1,5 metres, measured perpendicularly, above the roof and/or not more than 600mm above the highest point of the roof. Full building plans, including an engineer’s endorsement, are required if the panel(s) in its installed position projects by more than 1,5 metres, measured perpendicularly, above the roof and/or more than 600mm above the highest point of the roof.

  56. Hi Penny

    I recently purchased a house in cape town Milnerton area under a new development. been a first time buyer and a bit naive I did not know about SANS10400 regulations and have been trying to educate myself. I am specifically interested in the regulation XA2, (Hot water). Although not part of our plans the surrounding houses sold by other developers where built with solar geysers or heat pumps. Ours unfortunately does not seem to comply with any of the regulations mentioned. Can building plans be passed without compliance with SAN204 as mentioned above? is there any “body” that we can refer to that governs the regulations?

  57. Daan van Rensburg

    My impression is that Municipalities are allowed some leeway in enforcing National Building Regulations. If so, when did the City of Cape Town begin to enforce the amendments to the NATIONAL BUILDING REGULATIONS introduced in terms of GN R711 in GG 34586 of 9 September 2011, and more specifically, the regulations relating to ENVIRONMENTAL SUSTAINABILITY in part X, to which those new regulations relate.

  58. Hi

    Are you allowed to build a home theatre with no windows?

  59. Hi Pieter, I am sure that you can so long as there is adequate ventilation designed into the room and there are also adequate safety exit routes out of the “theatre”. A example in many buildings are the toilet facilities that have no windows but have plenty of ventilation channels and fans built in.

  60. The SANS 10400X & XA and 204 looks at the energy use in the building as a whole and a solar geyser is part of the overall mix to arrive a final compliant figure. I hope that the council approved plans that had this aspect covered. It seems as though those were extras that the other buyers would have had to pay for. Call the local council planning department and request that they have another look at your plans to see of they comply.

  61. Thanks for the feedback Stu.

  62. You have answered the question yourself, 2011 was when the new X & XA Environmental Sustainability and Energy Usage in Buildings were brought in to force and municipalities were allowed to enforce these regulations from that date.

  63. Hi Dean

    The date of the building plan application would lend some clarity as this law only came into effect in November 2011, with a 6 month “lead in” period. So if the plans for your unit had been submitted during this “lead-in” period then they may have (legally) overlooked Part XA. Unfortunately the industry is fraught with under-handedness, so the possibility exists that the contractor / developer simply didn’t install it as required. I trust you hadn’t taken transfer because the final responsibility always lies with the property owner. You could try the NRCS (National Regulator for Compulsory Specifications). Unfortunately they’re not really geared up for individuals. It might be worth paying a professional for an hour his/her time and issue a formal report in regards to your concerns.

  64. Just out of interest, if the PV panels are part of the hot water heating installation then SANS 10400 Part XA does require that the size and position of the installation (geyser as well as PV panels) be marked on the floor plans.

  65. Hi Neil

    This is unfortunately more typical in the industry than it should be – alterations being done without approved plans. On a slight tangent to this post, it is interesting to note that certain municipalities are happy to evaluate renovations separately from existing portions of structures. However technically speaking the law does require calculations to be done per floor level and therefore one alteration to one window should require the entire floor level to be re-calculated. Penny is correct in relation to the specification of the glazing needing to be correct. However one must remember that there are various influencing factors on whether glazing is compliant in terms of energy efficiency. So if the basic calculations show that reducing the window size achieves compliance then that certainly is one solution. However changing the glass, the window frame, adding shading, or any combination of these might also achieve compliance. In terms of your questions my response are as follows
    1) Is there an alternative to removing windows ( to save cost)? I know this question is linked to your suggestion about laminated films, however there is another solution besides this which would be more costs effective. One could undertake a formal Rational Design of the building. This is a far more scientifically accurate calculation method for achieving compliance with this law. It does cost more in terms of a professionals time input but usually arrives at spectacularly wonderfully results where (for example) you would not need to reduce the size of your windows NOR add any other interventions. So the cost of your professional consultant is made up for by the savings you achieve in not being forced to make these alterations.
    2) Perhaps a film type material to cover the windows? These laminate films are not as cheap as one might expect. Furthermore, you’d need a competent person who knows how to correctly factor in the values of the film into the total glazing value and then re-calculate the entire fenestration calculation.

  66. Hi Kuveshen

    2 points stand out for me.
    1) All hot water installations since 2011 require the installations of alternative water heating mechanisms. So your heat pump would have needed to be operational before the building inspector issued the occupation certificate. Further to this is the requirement that geysers and hot water supply pipes must be insulated. It’s not practically ideal that the geyser is external but technically, as long as it is insulated then it’s compliant.
    2) In terms of glazing, one must remember that there is a safety aspect to glass that is covered by Part N of the national standard. So 6.38 mm laminate glass may be required for certain glazed openings, even if not technically required for energy efficiency.

  67. Hi Meinhard

    This seems more like a misinterpretation of the law. I don’t have the wording at my finger tips right now but paraphrased it’s along the lines of, “A min of 50% of alternative hot water heating shall be provided other than electrical resistive heating”. Now an evacuated tube solar panel is still connected to a geyser which has an element (resistive heating). If one replaces an evacuated tube panel with a PV panel, it’s still connected to the geyser which stores heated water. The PV panel does not contain a resistive element but is simply powering the resistive element. This is the purpose of the law – to reduce our dependency on Eskom. A PV panel does exactly that as long as one can prove that it supplies a min of 50% of the heating requirement. One can try contact the NRCS (National Regulator for Compulsory Specifications) for an interpretation clarification. However they are not geared for individuals unfortunately, so it will be an uphill battle to get that clarification.

  68. Hi. Please let me know what the regulations are with regards to using gas cylinders in a block of flats. I would like to know about size of cylinders etc. Is there a document that can be forwarded to me.
    Also what are the laws for an evacuation plan for a block of flats with 64 apartments.
    Many thanks . Regards

  69. I am sure there are Farida, but not as part of the National Building Regulations. I suggest you contact the SABS (one of their libraries) and ask them to do a search to see what standards apply to gas cylinders. As far as an evacuation plan is concerned, this is a fire issue. Your local fire department should be able to refer you to someone who has the necessary knowledge. Again, it is not something that is covered by the NBR. SANS 10400 Part T: Fire Protection covers escape routes, exit doors etc. not HOW to evacuate.

  70. Neil,

    Check the total area in square metres of your fenestration (this is any glazed element such as windows or sliding doors, including the frame), versus the nett floor area (area excluding walls and stairs). A simple calculation may save you a lot of money: if the windows are less than 15% of the floor area, then refer the council to clause, which stipulates that buildings with less than 15% fenestration comply.
    It is one of the basic clauses of the new regulations that a lot of people seem to have overlooked.

  71. Hi,
    Does anyone have calculation for Heat Pumps to comply with 100% Energy Efficiency?

  72. Hi Liesl, Try John Douglas from His email is:


  74. Can anyone advise on which software has been accredited for the rational energy design and is a gas heater considered an alternative to solar and the heat pump alternative.

  75. I’m afraid I can’t help with software questions. There is surprisingly little guidance in the NBR XA that relates to water heating (which I presume you are referring to). Neither heat pumps or gas water heaters are mentioned. SANS 204 Energy efficiency in buildings gives a bit more info: 4.5.2 Hot water services A minimum of 50 % by volume of the annual average hot water heating requirement shall be provided by means other than electrical resistance heating, including, but not limited to, solar heating, heat pumps, heat recovery from other systems or processes. The solar water heating systems shall comply with SANS 1307 and SANS 10106, based on the thermal performance determined in accordance with the provisions of SANS 6211-1 and SANS 6211-2. The installation thereof shall comply with SANS 10254. Hot water usage should be minimized and the system maintained in accordance with the requirements given in SANS 10252-1. All exposed pipes to and from the hot water cylinders and central heating systems shall be insulated with pipe insulation material with an R-value in accordance with table 13. Insulation shall
    a) be protected against the effects of weather and sunlight,
    b) be able to withstand the temperatures within the piping, and c) achieve the minimum total R-value given in table 13.
    PLUS a whole lot more about piping and insulation.

  76. Please don’t shout Trevor. We don’t charge for information and so have to answer queries in our spare time. In any case we don’t have any information about software. Try Google or someone who offers rational design services in SA.

  77. If you use accredited software that guides you through the process and spits out a report afterwards do I still need a competent person to do the work?

  78. HI Trevor

    Don’t kow if you came right regarding your query of software. THere has been some confusion regarding what is technically termed a “Rational Design” so feel free to contact me if you still have this query 073 471 2444
    Regarding gas water heating, it is my personal view that it is in conflict with the primary purpose of energy efficiency legislation in South Africa which is to reduce greenhouse gas emissions. I think most local authorities wouldn’t raise an issue with gas heating because it clearly is not “electrical resistance” heating and you’ll probably find most consultants offering that service would also not make an issue regarding LPG based heating.

  79. Robin Thomson

    A gas heater is acceptable as alternative heating, as it does not use any electrical resistance heating.

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