A unique triple lens on a tube skylight product is only a marketing gimmick because:
- Each lens reduces the solar brightness (light) by approximately 6%
- Each lens only impacts the heat gain by less then 2%
- The goal of tube skylights is to increase brightness while lowering solar heat gain and the triple lens has a negative effect on this goal.
While window type skylights main design is to change the mood of a room through the view of the sky it is often ruined during the summer with blinds that are constantly closed.
The design of tube skylights it to provide the most light possible, evenly spread across the room while minimising the discomfort of heat.
This is easily recognise through the SHGC (solar heat gain coefficient – amount of heat through the product) vs the VT (visual transmittance – amount of light or solar brightness thought the product)
While adding layers of glazing will impact the SHGC it will impact the amount of VT – light more.
On a standard piece of 3mm clear acrylic material used in “triple lens diffuser” the the VT or solar brightness is lost by approximately 6% while the benefit gain of reducing heat gain is less then 2%.
Solatube’s unique tubing material is daylight selective which mean it transfers visual light into the home while absorbing and removing infrared heat out of the tube increasing brightness and removing solar heat.
This allows Solatube to provide a tubular skylight with the best VT/SHGC maximum light v’s the lowest heat in the world.