Maintaining internal lighting & temperature
Windows strongly influence the use of the building and the productivity and comfort of its occupants. The choice of glass has a direct effect on energy consumption in a hospitality venue or building. SANS 204, the South African National Standard for energy efficiency in buildings specifies minimum glazing requirements for all new buildings and building alterations. SABS Standards
The location and placement of windows in your building can dramatically affect your internal lighting and temperature. The type of glass used has a direct effect on heat retention and rejection plus natural light filtration. Critical to the overall performance of your glass is the type of frame and quality of installation (SANS 204 specifies requirements on the combined effect of glass and frame). There are specified requirements for each of South Africa’s climatic zones and similarly, there is specific recommendations for each African country’s climatic zones.
There are a wide range of new glass products and innovations available to improve the thermal performance, as well as the aesthetics, of your building.
Factors to consider regarding the characteristics of glass include:
- The U-Factor – sometimes referred to as U-value or thermal transmittance which addresses the ability of glass to harness and retain heat in differing climatic conditions.
- The solar heat gain coefficient (SHGC)– keeping harmful rays out and allowing for the correct solar energy absorption.
- Visible Transmittance (VT) or Light Transmission – eliminates the need for artificial light by allowing the right amount of light to enter the Building.
- The solar optical properties – refers to the transmittance, reflectance and absorption of light.
- The air leakage rating
- The condensation resistance rating.
- Appearance – aesthetic/artistic enhancement.