Installation of this type of attic ventilation involves leaving a gap in the sheathing along the ridge and covering it with a perforated vent.
Insulating attic with gable vents.
Covering up the soffit vents with loose fill or batts which can happen if you stuff insulation along the eaves is a huge no no.
The airflow from the soffits to the ridge vent keeps the roof cool and prevents ice dams and the material will block that flow.
The air is then exhausted through gable.
However if your attic has blocked soffit vents and is not well sealed from the rest of the house attic fans will suck cool conditioned air up out of the house and into the attic.
Never cover attic soffit vents with insulation use rafter vents and soffit vents to maintain airflow.
How to insulate an attic ceiling with no soffit vent.
For the same reason insulation shouldn t touch the roof s underside.
Before insulating vaulted attic walls you must provide an unobstructed route from the soffit vents to an exit vent to prevent damage to the roof from moist hot air.