Cathedral Ceilings need to Breathe.

All roofing systems need to breathe, this especially true of Cathedral ceilings.  In a Cathedral ceiling fiberglass insulation is sandwiched between exterior sheathing and interior sheet rock.  To ensure positive airflow builders commonly use EPS or XPS baffles to keep an airspace open from the soffit to the ridge vent. Well intentioned but woefully inadequate.

Those baffles work great in an attic, where they prevent clogging of the soffit in a very small 2 - 4 square foot area, but they are not designed to span the space between rafters, or be run end to end from the soffit to ridge vents.  Here they allow insulation to press against exterior sheathing or worse they are crushed and block all air movement.

MaxiVent is designed specifically to meet the unique requirements of Cathedral ceilings.  MaxiVent spans the entire width of the rafter ensuring that condensation will not be caused by water vapor laden fiberglass contacting the roof sheathing during cold weather. And because of its rigid laminated construction it is strong enough to retain its shape it will not be crushed like flimsy alternatives.

Ensure proper ventilation with MaxiVent, cathedral ceilings shouldn't get all choked up.