Sample Flat Roof microFIT Installation
Solar panels produce at their maximum when they are exactly perpendicular to the sun - give or take 15degrees. Having a panel just lay horizontal on a flat roof will give you power some of the time - like in the summer - but idealy they are mounted at an angle. In fact, the optimum angles when it comes to solar power in Ontario is 180degrees due south and 35degrees tilt.
In this example we used a Schletter flat roof racking system that allowed us to install panels 2 up at a 29degree angle. The 2 up design kept the costs down while the 29degrees give great energy capture. The high profile meant we had to space the 12 panel arrays such that there would be minimum shadow issues of front arrays on the back arrays.
This design too though has a high profile to the wind. Wind lift is the biggest concern with flat roof mounting and here Schletter provides their Windsafe design (see upper right picture) that cuts the lift by about half. In this case that reduces the stress on the roof connections and if this was a membrane sealed roof, it greatly reduces the amount of ballast required.