I thought I framed my rough opening properly but there's a huge gap in between the top of the door and the actual door frame itself. Can I just throw a 2x in there and nail it off?
Thank you!
If you are placing the door frame/ threshold right on a concrete floor/ slab that could get wet from rain, etc. I would recommend using some treated lumber 1“ x6” (actual 3/4 x 5-1/2” ) stock to set the door jamb on. The bottom of the door jambs are usually primed, but they will eventually **** up water and rot.
cut board to width of door opening, not width of door. This way depending where you place door in opening the bottom of the jambs will sit on the treated board. As far and width placement I have the board project 3/8” of an inch past the outside of the sill for caulking. I put down 3 layers of caulk on the concrete then the treated board and more caulk on top of board and set the jamb on that.
On my application the concrete walk is even with the garage slab, so I didn’t want that jamb sitting on the concrete.
On the top opening you can fill it as others had stated. Just make sure the brick molding or door trim the door came with is tight to the wall . Usually no nails in the top jamb.