As depicted by the pair of photographs above.
Debris in attic from ridge vent.
4 missing or blown out ridge vent letting leaves blowing up the roof get into the ridge slot.
If you were to install about 40 feet of roof ridge vent the area would span up to 10 turbines in this case 10 turbines would cost you substantially more to purchase and install.
The openings created between the lines of raised metal where they fit under the ridge cap provide ventilation to exhaust hot attic air.
But the ridge vent maintenance and running cost is a lot less than for turbines when.
However if you were only going to install 3 or 4 the turbines would be more affordable to you.
But if the slots are not sealed a brisk wind slides leaves up the roof and into the slots where they drop down to form a long line of debris in the attic insulation below.
With that belief snow plugging the ridge vent would seem irrelevant danh says ridge vents remain effective in winter because winds generally clear the ridge within a few days of even a heavy snow and because warm air working its way up through the attic will melt snow covering the vent.
3 ditto on missing screening on the eaves.
Soffit vents are one of the most popular intake vent styles.
They are easy to install under the roof s overhang which is known as the soffit are generally hidden from sight and provide excellent protection from weather outdoor debris and pests while still allowing air to flow into the attic.
2 missing screening on a gable vent unlikely unless on a dormer as a gable vent is normally a long way off the ground for leaves to be swirling around or entirely missing vent.