From our Wildlife Specialist:

Although the photos don’t show very well several areas of the body I’d really like to see, I believe this is a juvenile Eastern Ratsnake, a species that quite frequently finds its way into buildings/structures. More info about the species and numerous comparative photos can be obtained on the Virginia Herpetological Society web site (http://www.virginiaherpetologicalsociety.com/reptiles/snakes/eastern-ratsnake/blackrat_snake.php). Juveniles (heavily patterned with dark patches over a light background) look nothing like the adult stage (shiny jet black on top and white or light gray with kind of a faint checkerboard pattern underneath). It can take about 2 years to fully attain the adult coloration … this one looks like it’s starting that transition.

It’s not a venomous species, so there’s some relief for the affected client there, but, if cornered or threatened, it will strike and can deliver a rather nasty scraping type of bite (due to small teeth); they often carry a high bacterial load in the mouth cavity and in their saliva, so any untreated or uncleaned wound can get ugly and infected quickly. Best not to try to pick one up if you don’t have experience doing so … use a long-handled implement to carry it outside.

You also might remind folks that killing any snake in Virginia is an illegal act unless said animal presented an imminent personal safety threat (which obviously is open to interpretation). Nevertheless, all attempts to safely remove the animal without killing it is the intent of the regulation.