Fenestration and Glazing Guidelines
Fenestration Calculations (Glass size), Procedures, and Calculations.
Window area guidelines below
The guidelines featured in the pdf below give an idea to anyone wanting to calculate the Fenestration Compliance Procedures in terms of Sans 10400-XA:2011 and SANS 204:2011, what is required, and what is involved.
Step-by-step
There is a step-by-step guide to area (nett floor) calculation with reference to the parts of the regulasies that apply. A SGHC (solar heat gain calculator) is also supplied, to calculate the heat conducted in and out of a gebou. There are a couple of “real-life” calculations at the end of the document that illustrates how this was achieved.
Competent person
You will see that the window area calculations that need to be done to comply with the Regulations are not at all straightforward. But you do, in any case require a “competent person” to draw up your building plans, submit them to the plaaslike owerheid, and take responsibility for the project (including ensuring that konstruksie is in accordance with the plans).
A bekwame persoon should be well equipped to interpret fenestration and beglazing guidelines as well as procedures and the calculations. If not, it is the responsibility of that person to include someone who is in the project.
This extract below from “Specifile” will give you more info for your calculations:
It’s been just under three years since the SANS 10400 National Bouregulasies, covering energie usage in buildings, were amended in the form of the XA appendices. The aim was to further enforce and regulate energy efficient practices in the built environment, with the long-term benefit of reducing overall energie consumption and CO2 emissions. MORE…
The fenestration calculations relate to glazing – ie windows – as well as heating, ventilation, and air conditioning. Fenestration is as important to a house that incorporates electricity as a house that is off the grid.
What is the reason for having to comply with these fenestration rules when the house is not dependent on Eskom – using solar entirely?
Are fenestration calculations required for all council submissions?
Hi Tiaan
Perhaps there was confusion with fire regulations. National regulations do have fire safety distances in relation to neighbouring boundaries. Although Penny is quite right in stating that individual Local Authorities might have their own ordinances that have requirements of this kind. Not to mention, of course, that housing estates often have their own architectural guidelines within the estate that may enforce this type of consideration towards neighbours.
Hi Peter
Not sure if you received a conclusive since your post. SANS 10400 Part XA is quite clear about buildings having a window-to-floor are percentage less than 15% – they are automatically compliant with law and therefore no further technical calculations are required. Of course one should also factor in the regulations for natural illumination, which require a 10% ratio and therefore allows a very narrow spectrum of 5% for a total compliance. Anyway there are many alternative solutions to get the building compliant in every respect.
Yes you will have to get a professional to design the alterations and to do the fenestration calculations for you.
Please have a look at our page that I think gives you what you are looking for: fenestration-calculations
Haai daar,
We are building a new resedential house and we are concerned that we are having over budget for the fenestration on the new requirements.
1. Is the new regulation they fully enforced?
2. How can i get a free calculation sheet to work out some calculations myself.
dankie
Allister
I require some advice , I am planning a small a small extension to the front of my house ( moving bedroom walls forward by 1.5 metres. Do I require fenestration calculations to be done when I submit plans for the alteration .thanks
Peter you can get SANS 204 from the SABS – it is not available free.
Hi,
Where can I get a copy of SANS 0204 Energy Efficiency in Buildings, is this available on the internet?
Groete
Petrus
I assume so Peter
If we design a building to meet the 15% (max) for energy efficiency, is it still a requirement to prove the fenestration calculations?
Groete
Petrus
Hi guys you should check out http://www.sanscalc.co.za . Its a desktop application that does the job and makes it easy. There is also a cloud based version of SANSCalc to be released soon. Check it out here: http://online.sanscalc.co.za
You can register for a one year FREE license!
Cheers
Hi Hayley,
I wish that there was an easy answer, as the whole XA calculation criteria are quite complicated. The expert that I consult from time to time recommends for the easy calculation just to treat the area as a single storey. If you need your calculations done professionally then contact John at jdctri@gmail.com
haai daar
I just would like to know if the nett floor area for fenestration includes double volume areas?
Tiaan, I am not aware of any national building regulations specifically aimed to provide privacy to neighbours. However there are by-laws in various municipalities that prevent people from having windows in a wall adjacent to another property, if the building is closer than a minimum distance.
For example, the City of Cape Town’s Zoning Scheme Regulations that came into effect in March this year state (in terms of properties zoned single residential – i.e. conventional housing) that:
“Window and door placement
Any portion of a building which contains an external window or door facing onto a common boundary shall:
(i) be set back a distance of at least 1,5 m away from such boundary; and
(ii) the portion of building to be set back from the boundary shall include the door or
window, together with such additional length of wall as is required to make up a total minimum length of 3 m.”
Haai daar
I am planning on building a townhouse with windows on the side closest
to the neighbour per the houseplan. They built the house with these
windows missing stipulating that due to regulations on privacy
(neighbour wall is 900mm to mine) they are not allowed to put in these
vensters.
Does this comment hold any water?
Rgards
Tiaan
Hi Piet,
Yes the fenestration calculations apply to all buildings and are also regulated in terms of what a building is being used for. As your church is not essentially “a dwelling” there are other regulations that will have to be read together with these. The SANS 10400-XA also divides the country into climatic areas that also affects the answer. As you can see with the “Fenestration Calculations” and the other factors the answer is not a simple one. I suggest that you contact your local council and ask them or alternatively ask a “competent person” (draftsperson, architect or engineer) for assistance. You might have one in your parish that will volunteer to help.
do these fenestration calcs apply to a church building with an very high cieling of about 5 meter, in the same way as for a recidential dwelling? we want to add a small conference room of about 50 sqM to the complex. The church as well as the proposed conference room ar used only about once a week for 1 to 2 hours.
Robin we can only point you in the right direction. We are not experts in fenestration calculations or any specialized construction-related work. I suggest you contact a “bekwame persoon“.
all examples indicated show pitched roofs. Please indicate how the fenestration calcs are worked out with :
1. a parapet wall sloping at 17,5 degrees.
2. a double storey with similar parapet.
as can be seen from the above examples – if there is a window centrally positioned in the wall – how does one calculate the P,G and H values. smae for both cases ??