Buildings account for about 40% of all energy consumed in South Africa and their potential to save energy is huge.
The National Building Regulations (NBR) have been updated to include Part X, which addresses environmental sustainability, and Part XA, which establishes requirements for energy efficiency in new buildings and will come into effect from 10 November 2011.
In terms of the updated NBR, thermal insulation must be included in the design of all new buildings. This, in combination with other energy-saving requirements relating to the design and construction of buildings, will make it possible to save up to 78% of a building’s energy consumption – for space heating, cooling and hot water services.
The application of this new legislation is good news for the environment and will help all of us save electricity.
The National Standard SANS 10400 (the building code) covers different aspects of the construction and finishing of buildings and sets out the minimum standards that ensure the health and safety of the occupants in buildings.
SANS 10400-XA deals with the energy efficiency requirements of the building envelope, including: orientation of the building, floors, fenestration, external walls and roofs and ceilings. In South Africa’s six climatic zones, defined according to temperature and humidity variations, the regulations stipulate minimum R-value requirements for external walls, roofs and ceilings – the R-value being the measure of a given material’s or combination of materials’ capacity to resist the transfer of heat.
The installation of insulation material of the appropriate thickness and R-value, according to the climatic zone in which a building is located, will protect the building against heat and cold and so help to save electricity.
SANS 10400-XA also deals with energy efficiency in hot water supply systems and requires that a minimum of 50% of the annual average heating requirement for hot water must be provided by means other than electric resistance heating (conventional geyser) or fossil fuels. Options include: solar heating, heat pumps, geothermal heat, renewable combustible fuel, and heat recovery from alternative systems and processes. It further requires that all exposed hot water pipes with an 80mm diameter must be insulated with material providing a minimum R-value of 1.00.
Insulation is often considered a luxury and overlooked in home building, yet its primary purpose is to save energy and improve the home’s comfort. To insulate the ceiling and geyser system properly in a typical home costs less than 1% of total per square metre building costs, yet it will save money over the lifespan of the home.
A home without ceiling insulation typically loses and gains up to 35% of its heat through the ceiling. This can be reduced dramatically by installing insulation of the correct thickness.
Think Pink Aerolite from Isover is a thermal and acoustic ceiling insulation material that reduces the amount of energy required (for mechanical heating and cooling) to maintain a comfortable living environment and it offers a payback in less than two years, with continued savings thereafter.
Aerolite is produced from a combination of naturally occurring minerals such as silica sand, which is a sustainable resource, and up to 80% recycled glass, making this glasswool environmentally friendly and non-combustible. It also offers excellent sound absorption properties and is easy to install.
Aerolite is supplied in various thicknesses to meet the ceiling insulation requirements for buildings in each climatic zone, in line with SANS 10400-XA.
For hot water supply systems, Isover supplies a Geyser Insulation Pack and a Geyser Pipe Insulation Pack.
A geyser consumes 35% of the average household’s electricity. Electricity savings achieved by insulating the hot water system can vary depending on the length of pipes insulated, geyser thermostat setting and hot water usage.
Isover’s Geyser Pipe Insulation Pack consists of six one-metre glasswool snap-on pipes which are non-combustible and achieve an R-value of 1.00, as required by SANS 10400-XA. By insulating the hot water pipes you can save up to 37% of the energy used by the geyser system, achieving a payback within six months.
Isover’s Geyser Insulation Pack consists of a flexible foil-faced glasswool insulation blanket, tape and five one-metre snap-on pipes which are non-combustible and exceed the R-value requirements set out in SANS 10400-XA. By insulating the geyser and pipes you can save up to 58% of the energy used by the geyser system, achieving a payback, similarly, within six months.
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