How do you ensure you have adequate gable or soffit-to-ridge ventilation and what kind of company would I hire to asses that? The only problem with ridge vents is that they don’t work when covered with snow and ice, as mine are for the first time in 18 years. How are cathedral ceilings vented?
The snow will quickly melt at the ridge, so no worry there. A cathedral or vaulted roof has no separate attic to vent, but air circulation is still necessary. Venting this space is done by installing soffit vents, a continuous ridge vent, and then connecting the two with a series of baffle vents, installed within each rafter bay. In a vaulted roof, the soffit vent serves as an intake, and the ridge vent functions as the outtake, or exhaust vent. Air flows in the soffit vent, upward through the baffle vents, and out of the ridge vent. This cools the underside of the roof deck, removing heat and moisture that could otherwise damage the roof. Baffle vents also keep insulation from blocking up the eaves. Cathedral-ceiling venting is usually handled before drywall or plaster is installed. It is best done during new construction or when re-roofing, because it involves installing venting at the eaves, venting at the ridge, and new roofing at the ridge. While a roofer is best equipped to handle the ridge vent, a contractor or carpenter will do a better job retrofitting gable-end vents in your siding. Most roofers I know try to avoid dealing with siding and trim. So to answer your question: both are capable, but a carpenter will probably do a nicer job.