Many students report that going to a faculty member’s office for help is intimidating. If you hold office hours in a public space like a computer lab, students can work on their homework and get help when needed. A lab can also provide more space so you can rotate around the room helping students. It can also be helpful to be able to leave at the end of your office hours without having to kick students out of your office.
Example: "I hope you'll stop by my office hours in the computer lab tomorrow."
See this and related tips as a Tip Sheet: http://csteachingtips.org/tips-for-encouraging-help-seeking