Window type skylights aim to change the mood of a room by providing a view of the sky. However, this aspect is often ruined during summer with blinds that are constantly closed.
Tube skylights are designed to maximise the entry of natural light into interior spaces, with the light evenly spread across the room while minimising the discomfort of heat.
This is easily recognised by studying the SHGC (solar heat gain coefficient – amount of heat through the product) vis-à-vis the VT (visual transmittance – amount of light or solar brightness through the product).
When using a ‘triple lens diffuser’ on a tube skylight, the added layers of glazing will impact the SHGC, but it will impact the amount of VT even more.
On a standard piece of 3mm clear acrylic material used in a triple lens diffuser, the VT or solar brightness is lost by approximately 6% while the benefit of reduced heat gain is less than 2%. When tube skylights are installed to increase brightness and lower solar heat gain, the triple lens diffuser has a less than satisfactory effect, making it a mere marketing gimmick.
The unique tubing material in Solatube’s tube skylights is daylight selective, which means it transfers visual light into the home while absorbing and removing infrared heat out of the tube, resulting in higher brightness and reduced solar heat gain.
This allows Solatube to provide a tubular skylight with the most optimum VT/SHGC performance.
