The No Sky Line is an imaginary line within interior spaces which separates the zones which see the sky from those who don't.

It is frequently used, in particular in UK, in conjunction with VSC (Vertical Sky Component) and APSH (Annual Probable Sunlight Hours).

This makes a set of 3 indicators for early phases because they require little information.


This indicator indicates how much sky is visible in the field of vision of users.

It gives a very first insight of the quantity of light in overcast sky (before Daylight Factor can be calculated) and of the pleasantness given by the presence of the sky.


Easy NSL visualization inside Sketchup models

Every calculated surface is displayed in false colors according to the palette to allow immediate understanding of the results

NSL, No Sky line  in DL-Light

Detailled NSL results

The report window gives detailled results for each surface and can be easily exported.

NSL, No Sky Line in DL-Light