Careful attention to the design and selection of skylights is important as this will save energy, help to avoid problems and ensure a pleasing result for your living or working environment. The following factors should be considered to ensure the end result achieves light levels amendable to a safe and happy environment and the full potential of the product is realised.
When deciding on the type of skylight consideration should be given to relevant state, territory and local authority requirements.
Typically most of the statutory requirements are detailed in the Building Code of Australia (BCA). Assistance with the requirements of the BCA can be obtained from your local council building department.
Effectively skylight design can be based on empirical information derived from past successful installations, making due allowance for the deviation of the parameters of the new installation under consideration, such as,
a) Window Energy Rating Scheme (WERS) for Skylights
b) The size of the area to be lit
c) Ventilation Requirements
d) Fire Protection
e) Structural Considerations
f) The geometry of the shaft and shaft lining materials
g) Aspect and shielding of the skylight
h) Glazing and reflectivity of walls, flooring, furnishings and ceiling
i) Visual comfort
j) Light distribution
The parameters (other than the actual area to be lit), in the absence of measured data can be estimated and allowance made. The allowance can be generous as overestimation of required size is preferable and the associated cost increase will in most situations be very minimal. This approach will ensure success.
The more rigorous alternative is dependant on the availability of measurements and data to determine the physical parameters relating to the skylight installation including room served, orientation, location, product preference and the like in order to define the exact characteristics of the installation.
The reader who desires or needs a more scientifically based treatment is referred to “Skylight Handbook design guidelines” of the American Architectural Manufacturers Association. This publication provides a more detailed analysis of the subject.
Acknowledgements: Skylight Industry Association Inc.