Energy Calculations and Fenestration
The SANS 10400-XA standard is a compulsory standard implemented in SA to ensure all new habitable buildings comply with.
Almost 60% of the world’s electricity is used by residential and commercial buildings, making it a rapidly increasing and pressing matter of concern. It’s due to the global climate changes and an increase in costs and energy consumption requirements that the need for energy efficiency and energy-efficient buildings is being emphasized.  70% of South Africa’s buildings were designed and built when electricity prices were economical, but the constant price hikes are making it not only hard to maintain a livelihood but also depleting the energy resources at a very rapid rate. Thus, the increasing burden on the South African national electricity grid forced the government to make amends and introduce The South African National Standard – SANS 10400 – XA and the SANS 204 to regulate energy use and encourage energy efficiency in building for better utilization of resources and ensuring improvement in the ecological changes and declining ecosystems.
Energy-efficient buildings are a simple and very innovative idea to introduce required changes in the existing buildings and practical measures that save energy when new buildings are built and designed. Â With the introduction of new regulations and policy in the existing sans 204 and national building regulations, the government of South Africa is taking a step ahead towards making the country a cost-efficient country!!
Many modern and especially commercial buildings have been built without much consideration of passive design and rely strongly on technology such as Heating, Ventilation, and Air-Conditioning (HVAC) systems and electric heaters to provide a comfortable indoor climate. Using electricity for these functions is very inefficient and costly.
Â
What Is SANS 10400 – XA?
Â
The SANS 10400-XA standard is a summary of the SANS 204 and other standards into a single reference for homeowners to ensure compliance with the energy efficiency requirements of the National Building Regulations (NBR). Â These Requirements include:
Buildings should face north so as to make most of the sunlight along with suitable roof overhangs to maintain the adequate temperature during both summers and winters.
Use of energy-efficient heating, ventilation, and air-conditioning (HVAC) systems wherever required; Â
At least 50% of water heating must be done through a solar water heater or heat pumps or any other energy-efficient manner.
The SANS 10400-XA is part of the National Building Regulations (NBR) and must be adhered to. Municipalities are responsible for assessing and approving development applications including their adherence to the NBR.
Â
The SANS 10400–XA Regulations
Â
The latest amends in South African National Building Regulations (NBR) list the following regulations and adherence to which is mandatory to all homeowners.
XA1 – all homeowners must use energy efficiently and reduce greenhouse emissions and use energy within the given limits.
XA2 – not more than 50% of the annual volume of domestic hot water should be heated through electrical resistance heating, i.e., 50% or more of hot water used must be heated by energy sources other than electricity.
XA3 – compliance with the XA1 Regulations must be accomplished by one of three methods. If homeowners or competent parties build in accordance with SANS 10400–XA, then the buildings will be ‘deemed to comply’ with National Building Regulation XA1.
Â
Which buildings are affected by the SANS 10400 XA requirements?
Â
Buildings that consume energy as a result of human occupancy are the main target of the new regulations. All new buildings must comply with these regulations, and any additions or extensions to existing buildings must be strictly made in compliance with the new regulations. If the existing building is unaffected by an addition, only the addition will have to comply with the regulations.
Â
How is compliance achieved?
Â
To avoid delays in achieving planning approval and receiving occupancy certificates, homeowners should communicate to their architects and professional teams that the home must be designed in accordance with the SANS 10400–XA Regulations. Compliance with the SANS 10400–XA Regulations requires that the design of new buildings satisfy certain conditions. There are basically three routes by which homeowners can comply with the new regulations, these three routes are-
The Prescriptive Route
The Reference Building Route
The Performance Route
The Prescriptive Route is generally available to all persons and will commonly be used for houses and smaller buildings. This route requires that a set of rules is adhered to for water heating, insulation, and glazed areas, i.e., windows, glass doors, and roof lights.
Homeowners need to choose the most practical and cost-effective route, depending on their financial resources and project timelines.
Â
What documentation must be completed?
Â
Once the plans are ready for submission, the Appointed Person (or Responsible Person, if a professional has not been appointed) must inform the local authority and Building Control Officer which compliance route has been chosen, by completing a set of four documents (Forms 1 to 4). These forms can be downloaded from the SABS website (www.sabs.co.za).
Â
FORM 1: DECLARATION BY THE HOMEOWNER FOR APPROVAL OF BUILDING CONSTRUCTION.
Â
Mainly the roles and duties of the homeowner are discussed here. The competent person making a declaration wherein the means for SANS 10400 -XA regulations have to be satisfied.
Â
FORM 2: APPLICATION FOR APPROVAL AS AN APPROVED COMPETENT PERSON.
Â
In this step, the Competent Person agrees to take on full responsibility for all the energy-related duties in this section the competent must declare that he/she has the qualification, knowledge, and contextual experience necessary for completing the work with compliance to the regulations.
Â
FORM 3: DECLARATION BY A COMPETENT PERSON.
Â
Under this the Competent Person is required, to make a declaration that the person is the best for the task at hand and has strictly adhered to the regulations. This form also has the second part which states the critical design information of building and its energy consumption.
Â
FORM 4: CERTIFICATE OF COMPLETION BY OF THE STRUCTURAL, FIRE INSTALLATION, OR FIRE PROTECTION.
Â
Here, the Competent Person has to make sure that he/ she has completed and attested the Certification of Completion. It is also the responsibility of the approved competent person who will retain the role of seeing all the energy aspects of the project.Â