I currently have two 4 ft long off ridge vents opposing each other. My roofer suggests I remove the two and place one off ridge vent on backside of hip roof. My question is, will that be enough ventilation with my soffit vents?
Impossible to give an accurate answer with just that. Pictures might help.
I’m not sure about the terminology you used but 2 four foot sections of ridge vent wouldn’t have been enough exhaust ventilation for anything but shed. Go to lomanco.com and use their online vent calculator to determine the amount of ventilation needed for your roof. I’m not a fan of hip ridge vent but it may be your best choice.