How do you use an old work box?

Insert Old Work Box Into Wall Hold the box so the mounting ears on the front of the box are tight against the front of the drywall while you tighten the two retention screws. Turning the screws will flip the retention tabs so they can then be drawn against the back of the drywall, securing the box to the wall.Click to see full answer. Likewise, what is an old work electrical box?An old work box is an electrical box for light switches, outlets, and other devices that are installed after drywall has been installed on the wall studs. The term old work (sometimes old construction or retrofit) refers to walls that are already covered up, making it impossible to access the studs.Furthermore, what are the types of electrical boxes? There are round, square, retangular, shallow, weatherproof, and extension boxes. Electrical boxes come in plastic and metal varieties. Plastic boxes are non-conductive and are relatively inexpensive. They come in different styles that either nail on or are the cut-in variety. Subsequently, one may also ask, how much weight can an old work box support? 50 lbs. What is the difference between old work and new work electrical boxes?Whatever the material, electrical boxes can be loosely divided into two types: New work boxes, designed to be installed just after the wall is framed but BEFORE the surfaces are finished with drywall. Old work (also called retrofit) boxes, designed to be installed AFTER the walls are finished.