All of my bedrooms have 36" cupboards with bi-fold doors that I want to replace with two 18" double-doors. All of the door jambs are covered in 1/2" drywall. I've made a few test holes and there seems to be solid wood behind it, but I don't know if this is just some 2x4's or if it is a solid piece more appropriate to be exposed as a jamb.
I will be installing trim around the door once complete. The depth of the current frame (drywall to drywall) is 5 7/8".
Buying two 18"x80" doors is preferred since they are cheap and available at my local home improvement store but I am willing to compromise.
I'm looking for what is the best way to prepare this frame in order to hang doors. My first instinct is that I need to remove the drywall so that I can properly mount and mortise the hinges, but I'm not sure... Things I have considered:
1) Removing the drywall, finding lumber that has a nominal thickness of 1/2" and having it ripped to 5 7/8" and installing it as a jamb on each side. I don't have a table saw (yet) so this this either means careful work with a circular saw or paying a store to do it..
2) Installing the same type of wood as above on top of the drywall and buying custom sized doors
3) Taking the really lazy way out - use non-mortise hinges right on the drywall. I know I'll regret this.
Am I missing something obvious or easier?