Question Up Front
Why are door trims at the floor not cut at 45° like everything else is? Is it a style thing, or is there a functional reason for it?
Details
I have noticed in many houses that the baseboard is mitered and beveled so that the pattern of the baseboard continues seamlessly.
Example
The bisecting miters and bevels seem to be everywhere except for the bottom parts of doorways. The example below shows a doorway with a different trim than the baseboard, but it doesn't seem to matter whether they're different. The bottom of the trim is always cut at 90°, not 45°.
Example
Is there a functional reason for this, or is it just a ubiquitous style?
Best Answer
The issue is that normally, moldings around a door are very different from baseboard molding. You can easily bevel two identical moldings together; you can't do the same if the profiles are different.
Of course, this begs the question: why are door moldings different from baseboard moldings? Well, mainly tradition; that's the way it's usually been. Lee Sam's answer that "doors are in the wall and baseboards are on the wall" is probably as good as you'll get.