I have to use a pre-primed wood interior door as an outside door. I'm wondering if I should add a coat of exterior primer, or just paint it with the finish colors. Thanks in advance.
It won't really matter as using an interior door outside is a doomed enterprise.
And though Casey is most likely dead-on, it never hurts to prime the so-called pre-primed doors. Since you're using it as an exterior door, you might as well use an exterior primer under your exterior paint.
Some of the first apartments I looked at had interior doors for the front door. My parents said no and drove to a different part of town to look...
Some of us parents actually are smart.
If it's a hollow door...obviously forget it!!
If it's a cheap pine door....forget it!!
IF it's a decent solid door, yes...scuff-sand thoroughly and re-prime ALL sides.
THEN 2 coats of new color, at least Satin sheen.
"Some of us parents actually are smart."
Indeed! Though back then I was just upset that living in a nice apartment meant I couldn't have a pet. ;)
Don't bother painting it at all. It will not last more than a couple of years no matter what you do to it.
And why do you "have to"?