Va. Code Ann. § 55-248.13:1

Peepholes!

... any landlord who rents five or more dwelling units in any one building shall install:

1. Dead-bolt locks which meet the requirements of the Uniform Statewide Building Code (§ 36-97 et seq.) for new multi-family construction and peepholes in any exterior swinging entrance door to any such unit; however, any door having a glass panel shall not require a peephole.