Roof light

for the purposes of Section J and Part F4 in Volume One, and Parts 2.6 , 3.8.4 and 3.12 in Volume Two, means a skylight, window or the like installed in a roof—

1. (a) to permit natural light to enter the room below; and
2. (b) at an angle between 0 and 70 degrees measured from the horizontal plane.

for the purposes of Part 2.6 and 3.12, means a skylight, window or the like installed in a roof:

1. (a) to permit natural light to enter the room below; and
2. (b) at an angle between 0 and 70 degrees measured from the horizontal plane