Basements, Attics and Crawl Spaces - Attic venting

I have an attic project in mind and I just noticed my house, a cape built in '65, has no soffit vents. The roof is gabled (I think that's the correct term? - steeply slanted) and dormered in the back and there are two bedrooms upstairs.

How important is it to add vents? My project entails turning the wasted space under roof into insulated storage and closet areas. The house isn't all that big so I'd like to use any space I can.

Thanks...
Craig in NJ

Capes are difficult to properly ventilate attic spaces. But in this climate, attic ventilation is a must, in winter as well as summer. Soffit vents don't work well in capes, too much going on in between the soffit and the attic. Gables vents and ridge vents are needed to move hot or moist air. Proper insulation will reduce moist air in winter months(seal all openings from the living space) and improve things in the summer. Bath exhaust fans MUST exit to the outside. Plug wire holes, etc.

If the OP has a full dormer in the back soffit vents can be installed. On the pitched roof side the insulation will block any air flow unless there is enough access to allow the installation of vent baffles. A ridge vent is probably the way to go.

How do you plan to insulate this space?

Thanks for the replies. Before I discovered the lack of vents in the soffit, the idea was to install baffles along the roof slope up to where the bedroom ceilings meet the walls - about ten feet per rafter. On top of that would go fiberglass insulation.
It means a lot of vents but overall I think it's worth time and expense; there's a lot of space going to waste in a relatively small house.
If there's a flaw in the plan would someone let me know?