I want to replace my exterior back door with a new model/etc of the same size. What I'm wondering is if I have to replace the frame of the door as well or can I simply just buy the door and bolt it in? The door size is typical/standard back door size.
What should I consider doing? Replace the whole thing or just the door? Any opinions?
It will often cost less to replace the door and frame as a unit. Custom-fitting a door is a fussy process. A pre-hung door and frame as a pre-matched set is a factory-built item. If you can get over the horror of ripping the frame out, it's generally faster to complete the job, as well.
However, if your doorframe is an architecturally significant old thing, replacing just the door may be the better approach - most new doors & frames are best for replacing cookie-cutter ticky-tacky doors and frames as found on many, but not all houses; they will look just the same, in most cases. [pun intended - RIP, Mr. Seeger]
It is far easier to replace just the door, as long as the frame is in good shape. You avoid all need to interact with the siding or weatherproofing of the home, for example.
Cutting the door can be fussy, but a good lumberyard (or perhaps big box) can help. You'll need cuts for the overall frame (not necessarily square), hinges, and doorset lock.
