Question: This spring I will have to replace a 20-by-16-foot patio roof. Visiting the various home improvement centers, I came across two products that appear to be suitable: Filon panels and Alumax. The latter appears to be mainly for commercial, residential or farm use. However, the salesman assured me that it is frequently used for residential patio covers. I have just retired and my wife and I plan to spend many hours on the patio. I've had cataract surgery and my eyes are sensitive to ultraviolet light. What's your suggestion?
Answer: Filon is the brand name of a widely used fiberglass panel for carports and patio roofs. It's so widely used that many contractors use it as the generic term for all such panels. I have a patio cover roofed with Filon panels. It's stayed in place under very windy conditions, thanks to care in fastening the panels to the patio cover structure. I'd recommend this product without reservation.
Alumax Building Products manufactures the Alutwin aluminum and painted aluminum roofing and siding panels. You enclosed a photocopy of the brochure for this product with your letter. I wouldn't hesitate to use Alutwin panels on a patio cover on aesthetic grounds: the panels are attractive and are available in many colors. My main objection is the lack of light transmission. You might end up with a too-dark patio. Using fiberglass panels like Filon allows you to control the light and solar energy transmission levels.