Doors and Windows - Making jambs - cut one too short.

I am framing out an interior door. Its an odd size created due to an extension so Im not going to buy one. Im going to make a set of french doors for this 32 inch opening (ill use paint grade plywood and put glass panels in the middle).

In any case, Im in the framing stage now and am putting up the jambs.

I measured my height at 6'8 and then, without thinking, cut it at 68" So now, one of my jambs is cut about a foot too short.

I dont want to go get another piece so Im thinking I can glue and screw these together. Id put a joining strip in the back and screw from the back so all you would see is a seam about a foot from the bottom. Since Ill be painting these , I can clean up the seam (which is pretty clean anyway) with putty if needed. So, I think it would look fine - unnoticable.

I shouldnt have to dowel or biscuit these, right? If my joiner is 12 inches long in the and the same depth as the jamb, that should be ok, right?

Any other issues that could come from this? Is it weakened at all? The seam is just above where the bottom hinge would go. I think Ill be fine but just want to check.

PS. The reason it is french doors for such a small opening is that it is an opening onto a small balcony. I figured a regular swinging door would look odd. A thin set of french would look nicer.

I am framing out an interior door. Its an odd size created due to an extension so Im not going to buy one. Im going to make a set of french doors for this 32 inch opening (ill use paint grade plywood and put glass panels in the middle).

In any case, Im in the framing stage now and am putting up the jambs.

I measured my height at 6'8 and then, without thinking, cut it at 68" So now, one of my jambs is cut about a foot too short.

I dont want to go get another piece so Im thinking I can glue and screw these together. Id put a joining strip in the back and screw from the back so all you would see is a seam about a foot from the bottom. Since Ill be painting these , I can clean up the seam (which is pretty clean anyway) with putty if needed. So, I think it would look fine - unnoticable.

I shouldnt have to dowel or biscuit these, right? If my joiner is 12 inches long in the and the same depth as the jamb, that should be ok, right?

Any other issues that could come from this? Is it weakened at all? The seam is just above where the bottom hinge would go. I think Ill be fine but just want to check.

If you want the best fit, you can use a biscuit joiner or a dowel. I don't think it's necessary. You might notice that a lot of door frames are cased with joined pine - not single pieces. Also, door jamb repair usually involves cutting off and repairing a piece of door jamb with a new piece of wood. What you're doing is ultimately no different than this. You have a better idea than I of which piece exactly you're replacing and what its structural significance is, but there is a very good chance that your piece of wood won't be load bearing.

Consider your average door. The majority of the load bearing is done by the surrounding framework. Your 2x4 door frame will support the majority of the house or surrounding structure. They in turn support the door jamb, of which the upper part supports most of the door.

In short, what you plan to do should be fine. I'd be more concerned that your jamb extension is securely fastened to what's behind it (the frame) rather than what's above it (the jamb).