Without knowing the age and condition of your home, it's hard to give a definitive answer. Hollow core doors date to the late 1950s. ( But I've seen 19th Century homes "improved" with hollow core doors.) I'm presuming there has been minimal settlement.) Some indicate that they would replace the doors and use the existing jambs. Is this doable? Would the weight be OK for the existing jambs? Panel Solid Core Door. Handle and rosette:Emtek sandcast bronze with "living" finish. Yes and yes. But there will likely be repairs to the jambs, as solid core doors require three-four hinges per door and the screw holes will likely not match the existing ones. pre-hung inserts....? All the pre-hungs I've seen use low quality hinges (usually the radiused ones) and are designed for installation by unskilled labour and high production. I would avoid them, even if they are available. If you use pre-hungs, there will be a lot of repairs necessary--casing, drywall and painting on both sides. A panel door can be solid-core or hollow. The key to this job is a skilled finish carpenter who will be able to adjust minor irregularities as a result of settling and the like. I would insist on seeing examples of his work. This is a major investment in materials that should not be left to a "handyman."

Yes doors are beveled along the latch side so the leading edge clears the jamb. This bevel is much more crucial with narrow doors than wide ones because of the geometry. Its also crucial with very thick doors. If your door was hung with the bevel backwards, by the time the bevel is put to rights, it will be too narrow. Don't worry about the bevel right now; If the edge is binding, have just enough planed away so it's 3/32 clear of the jamb at its closest point. Casey

Cutting the door frames to meet the floor is much easier than cutting the floor to match the door jambs. Do the floor first.

A door to a garage is not allowed to connect to a sleeping room and it would only need to be fire-rated if some unusual code applied (like the UBC or NFPA 101, etc.). The typical residential code requirement (IRC and its predecessor CABO, etc.) is for a solid wood, a honey-comb or solid core steel, or a 20-minute fire-rated door so it is usually possible to use an ordinary solid core wood door with an ordinary wood frame without rated hardware and without an automatic closer. (If you use a 20-minute rated door the frame and hardware should be rated/labeled/listed as well). It is always wise to ask the local building official; I've run into some who also like to enforce NFPA 101 but some aren't concerned about the pairing of a rated door and an unrated frame. These doors are not usually located in fire-rated walls (usually only the finish on the garage side is required to be rated board, if rated at all) so, making the doors carry a fire rating label from a testing agency makes little sense. Typical garage separation walls are, in reality, smoke partitions and the doors should be considered smoke doors. Therefore a more pertinent requirement would be for door gasketing which some jurisdiction do require. The risk of fire in a garage is far less than in a kitchen or bedroom. The requirement for a quasi smoke partition and door are due to the fact that a fire might not be detected as quickly in that location as in occupied parts of the house.