Solatube® Daylighting Systems vs flexible duct systems
Independent tests have been carried out by the Building Research Establishment (BRE) between Solatube® Daylighting Systems, which use only rigid tube material, and two widely-available flexible tube systems. All systems were tested under overcast sky conditions and simulated sunlight conditions. The results, summarized in the illustrations below, show a dramatic difference in the amount of light delivered.
Why do the flexible systems perform so poorly?
As you can probably appreciate, flexible tube by its very nature is not a reliable means of transferring light; light entering a flexible tube will not necessarily continue to bounce on a downward path, but will scatter randomly in all directions (including upwards) as it bounces off the concertinaed surface of the tube.
This scattering of light will significantly reduce the amount of light delivered to the room below. A rigid tube, however, removes the 'scatter effect' so significantly more light continues on its path to the room below. Solatube® Daylighting Systems use only rigid tube material. Our tube material is made from 99.7% reflective Spectralight® Infinity. It is the most reflective material used in any tubular daylighting device – rigid or flexible.
Easier to fit?
There’s a preconception that rigid systems are harder to fit. Not true; to achieve any chance of being able to transmit the best (for a flexible tube!) level of light, the flexible tube has to be pulled very tight to eliminate the 'creases' in the tube and then be very firmly fixed to the ceiling and roof connections. In practice, this can be very difficult to achieve. One of the advantages you’ll discover with Solatube® Daylighting Systems is that the high quality and design of the components invariably means that the job is easier than with lower quality, less well-designed products.
Flexible duct systems can be more costly than you think ...
Whilst flexible duct systems may be cheaper to buy, you could find that the cost to your reputation proves to be a price not worth paying, and the last thing that a professional builder needs is an unhappy customer. Our case study below shows just one example of poorly-performing flexible duct systems that have been replaced by Solatube® Daylighting Systems.
Solatube® saves the day for a Surrey builder
When a couple decided to extend their modern detached home in Chobham, adding an extra bedroom on the first floor meant that the former landing window would be replaced by a door into the new room, and that the landing would have no access to natural light. Their architect suggested using a tubular daylighting device to overcome this problem.
Although the builder, Peter, who had been contracted for the extension, had never fitted a tubular daylighting device before, he took advice from his local building materials supplier as to what he should purchase. He was told that a tubular daylighting device with flexible rather than rigid tubes would do the job.
Trusting this advice, he fitted two flexible duct daylighting devices. His customers, however, were very dismayed with the results. Rather than a landing flooded with natural light his customers told him: "Even on bright days there is very little light in the landing and we are extremely disappointed."
His customers decided to look around and see if there were any better products available and discovered Solatube® Daylighting Systems. Peter was asked to remove the flexible duct daylighting devices and replace them with Solatube® Daylighting Systems. He discussed his requirements with the Solatube technical team, and learned that just one of their products would be required to transform the landing owing to the higher performance and quality of the Solatube® Daylighting System. When the Solatube® Daylighting System arrived, Peter instantly saw it was a much higher quality system and began installation. He was delighted with the results.
Peter's customers were also delighted with the Solatube® Daylighting System and the amount of light delivered compared to the two flexible tube systems.
Quality is high on the agenda for Solatube® and this can clearly be seen from the quality of components and materials used in our systems to the outstanding performance you get from a Solatube® Daylighting System.
