Adding natural light to a space is a great idea for adding comfort to the occupants. But that doesn't mean you need to also bring in heat and UV rays. Learn how Solatube products bring the daylight without these potentially damaging elements.
One key performance indicator is the Solar Heat Gain Coefficient (SGHC) which measures how well a product blocks heat from the sun. For the majority of the year, especially in warm summer months, solar energy that is allowed to enter a commercial building unchecked can lead to a rise in the thermal load. This may require an increase in air conditioning usage and/or the addition of supplemental equipment to manage the added heat. Besides the added cost, air and radiant temperatures may be a factor on whether employees should be working or not.
The SGHC is represented as a number between 1 and 0, where 1 is the highest amount and 0 is the lowest amount of solar heat that can enter through a fenestration product. For example, an SGHC of 0.30 means that 30% of the heat available from the sun is transmitted through the fenestration system. Thus, a system with a rating closer to 0 is more effective at blocking the solar heat. The National Fenestration Rating Council (NFRC) establishes uniform product ratings and testing protocols for defining and reporting a product’s SGHC performance value under specific reference test conditions. Reputable products will have NFRC-certified SHGC ratings that are posted on the NFRC Certified Product Directory.
Independent building studies indicate that the most effective way to manage solar heat gain is to prevent solar heat from entering a building in the first place. Our Spectralight Infinity Tubing transmits the visible spectrum of light (400 to 760 nanometers), but provides significant blockage of Infrared (IR) wavelengths greater than 900 nm, which is the main culprit in solar heat gain. As a result, the SHGC is greatly reduced which, in turn, will lessen the air conditioning load requirement for the space being lit by daylight. These technologies provide the highest light output performance with minimal thermal impact.
Along with blocking a significant amount of IR wavelengths, Solatube Tubular Daylighting Devices also prevent virtually all UV wavelengths from entering the TDD system. This is important because UV light can have a negative impact on building materials it contacts—like carpet, clothing, and furniture. Without the right UV inhibitors at the dome level any material exposed directly to UV will deteriorate. As a result, Spectralight Infinity Tubing is protected from UV light through uniquely engineered materials in the optical domes.
Visible Light Transmittance with UV Blocking
Independent test results have shown that our products allow in the full spectrum of visible wavelengths of light that provide clear vision, but block virtually all of the ultraviolet wavelengths that can degrade building interiors.
Degradation of the tubing is virtually impossible because the specially-formulated, protective acrylic outer dome that captures the sun’s rays also has special UV inhibitors designed to block 100% of UVB (280 to 315 nm), 100% of UVC (100 to 280 nm), and 98.5% of UVA (315 to 400 nm) rays. In addition, Solatube tubing is specially engineered to be optically transparent to UV, preventing UV wavelengths from being reflected and/or transferred into the building’s interior.
Third party testing of Solatube Spectralight Infinity Tubing material through 3M’s advanced optical test laboratory proved the validity and reliability of its superior reflectance characteristics for both initial and sustained performance. When used in Solatube products' uniquely engineered daylighting system the material provides consistent and sustained Specular Reflectance and has for over 20 years in the field.
This means building interiors will be protected from fading and other degenerating effects because the UV will not be able to penetrate through the system.
Solatube Daylighting Systems use a proprietary capture-transfer-delivery process to deliver natural light to places that were once thought impossible. Our products combine patented technologies with progressive engineering for daylighting that delivers a superior blend of illumination intensity, thermal performance and light consistency. Our systems are easy to install, often requiring no structural changes, and are virtually maintenance-free. The fact that they are also energy-efficient, eco-friendly and affordable makes them the ideal choice for any commercial application.