Oil canning is an inherent part of light gauge cold formed metal products, particularly those with broad flat areas. Oil canning is defined as a perceived waviness in the flat areas of metal roofing panels. It can be more apparent during certain times of the day and in certain seasons based upon the angle which sunlight hits the roof and/or wall, and based upon the temperature differential.
Since many uncontrollable factors are involved, no manufacturer can realistically assure the total elimination of oil canning. Oil canning is not grounds for panel rejection.