Porch Ceiling Ventilation?

I'm getting a house ready to rent for the first time and was wondering what to do about these approx. 3' x 4.5' openings in the ceiling of the enclosed back porch. (I use the term "enclosed" loosely here...the only "wall" between this porch area and the outside elements is cedar shingles with the occasional hole letting daylight in. It started out as a proper enclosed porch project about 50 years ago which never got finished. The space basically serves as a framework/support for a outermost back door to the dwelling and as housing for the washer and dryer. It's not connected by ductwork to the central AC unit but is wired for just the laundry appliances.) The house was built in about 1944 and had an attic fan at that time but this fan is long gone. My question is -- Can I just close up these openings with ply board or does the attic still need ventilation from this area which would require putting up screens again? Thanks...