WOOD RACK SCHEMATIC

The following is a simple schematic of a "stick-built" wood rack made from 4x4s, 2x4s, and 1x4s.  Always use pressure-treated, outdoor-rated lumber and either stain or paint it as well to maximize durability. 

Once the rack is built and before the panels themselves are attached, we recommend the use of corrugated sheets under the panels to offer more long-term support.  Over time and especially during stagnation periods, plastic panels will conform to the surface they are mounted to.  They will tend to sage between the 24" gap between the 1x4 stringers of this rack design causing potential abrasion at the corners of the 1x4 and create potential drainage issues on shallow rack pitches.  To keep a clean, tight appearance and avoid these issues, lay inexpensive corrugated fiberglass, or carbonate sheets under the panels.  Avoid using PVC sheets since they will readily deform with warmer ambient air temperatures plus the weight of the panels with water.  Corrugated sheets are available at any hardware or building supply such as Home Depot, Lowe's, etc.  They typically come 8,10, or 12' long and  26"  wide so you will need two per panel overlapped to get the recommended 45-46" in width to fit just inside the panel width.  Their overall  length should be trimmed to fit inside the panel header. Keep this corrugated material out of UV radiation if not rated for such exposure.  These sheet will also minimize convection cooling off the back-side of the panels if any wind blows from that direction.  Convection cooling can reduce the performance of the solar panels.  Attach these sheets to the rack in two place to keep them from sliding out from under the panels.  The panels "belly-band" strapping will secure them otherwise.