Constructing a door frame

No. Just use a few more wall fixings. Don't forget packings or point up the gap between door and frame and let go hard before hanging the door. The main factor will be the thickness of the wall it's going into.

Are you making a door frame (extrnal) or a door lining (internal) ?. I assume the latter.

Former, difficult without proper woodworking kit, ideally a spindle moulder or half inch router with bench, assuming you want it to look OK with nicely bevelled corners and sloping profiles.

Latter. Modern door linings are typically 28 mm thick by 115 mm wide (for a 3 inch wall) or 135 mm for a four inch wall. Unless they are pre-rebated a modern door lining is just three bits of timber with the door stops nailed on afterwards.

It might look nicer if you had a proper door lining in-fitted within the existing frame and use some mouldings to bridge the gap.

I mean the bit twixt door and walls that you screw your hinges in to. This sort of thing.

The kind of frame I'm thinking of will be mostly hidden by facings and door stops. No fancy bits needed.

The existing one is rotten at the bottom and has a redundant window above the door. It'll be easier to rebuild the whole thing I reckon than arse around chopping rotten bits out and trying to make good.

Tim

Last door (and a half) that I fitted, I made the opening with sawn 4x2 which was plenty sturdy enough, and a casing-kit which was ready planed, rebated and rabbeted from B&Q. Came out mm perfect (perhaps a smidge too close, it's started to *just* catch in the recent hot weather).

Sounds tempting. The door we're planning on using is an original (100 yearish) panel door. Dunno whether casing kits will come in the right size. Will need to get daughter to do some measuring.

Tim