Understand what a prehung interior door is, how much it costs, standard sizes, frame types, and how to install it properly. Expert guide for buyers and DIY installers.

Measure the rough opening width (distance between studs) and height (sub-floor to header). Make sure you measure to the framing, not simply the old door jamb. You may have to cut away overhanging ...

In window and door installation, they’re often used to make sure the jamb is square inside the ... creating the thickness of two shims. This dual-shim method also provides a flat surface to ...