Square Skylights - Options Square Skylights - Dome Options Opal (Acrylic or Polycarbonate) Light transmission - 79%. Suitable for the majority of situations. Clear (Acrylic or Polycarbonate) Light transmission - 92%. Suitable for situations where shaft lengths exceed 3m, or other conditions that reduce available light. Heatstop (Specialised Acrylic) Light transmission - 51%. Suitable for extreme situations only. Roof Types Our square skylights are available for all roof types. Diffusers 1. Pattern 12 - Clear or Opal Acrylic or Polycarbonate. 2. Pattern 15 - Clear Acrylic. 3. Seadrift - Clear Acrylic. 4. Glocell - Opal Acrylic. Flat opal acrylic with no pattern is also available. Flexi Ducting For use with Direct Skylights brand ColourBond Ducting For use with Direct Skylights brand also used with Sunlite brand. Coreflute Ducting For use with Sunlite brand. Leadlights Enhance the beauty of your Skylight with the addition of an optional Leadlight Diffuser. Electric Exhaust Fan To reduce the amount of fixtures on your ceiling, and exhaust fan can be mounted to the dome of the skylight. Safety Bars Bars may be required on commercial situations if the skylight is large and on a trafficable roof. Not normally required for domestic applications. Shade Control Louvres Control the amount of daylight coming through the skylight with these pull string operated louvres. Ideal for bedrooms and theatre rooms. Electric Light Skylights can be illuminated at night by utilising electric light installed inside the skylight.