ABSTRAKThe current Indonesian standard for daylighting in buildings, SNI 03-2396-2001, recommends the use of sky component from a sky as the metric for indicating indoor daylight availability. To calculate sky component as a function of the relative position (L/D and H/D) of an unglazed, vertical daylight aperture, a reference table are provided; however, the accuracy of the tabulated values are unknown. This article reports the accuracy of the provided values compared to the analytical ones. It is found that 11 from 361 provided values have relative errors of 10% or larger. Comparisons between results of some worked examples obtained from interpolating the table values and from solving the analytical expression are also reported. based on analisis that recommended to use the reference table only if the L/D and H/D ratios are within the tabulated range of 0.1 ~ 6.0. otherwise, the use of analytical expression to determine the sky component is strongly suggested.