The more shallow the roof pitch, the greater the risk of ice dams. Excessive flex ducts allow additional unwanted heat to enter the attic space. However, when the light fixture was utilized with snow cover on the roof, additional heat was generated in very close proximity to the low sloped roof, causing pre-mature ice melt and ultimately an ice dam. Other portions of this roof's ridge vent had both felt paper and shingle materials covering the opening, thus reducing exiting net free-air flow. Without exits for attic air, heat builds up, melting snow, creating ice dams and causing many other problems, too.
Homeowners often create the perfect medium for mold growth - dark, moist, heated space.
The black area above the yellow insulation is not black due to a lack of light. Concerned about low humidity, he turned the central humidifier to maximum. Unfortunately, his builder did not install proper ventilation, either. Oh, if you have gable or roof vents, please don't cover them with plastic. Now you know things not to do , so let's discuss things to do about excessive heat.