Rotten base of door frame

There are always ways of doing this Matt...but even to do a reasonable repair, its often quicker to start again and do the job properly.

Wouldn't take much to unscrew the upvc frame, take it out and fit a new timber frame, then put the upvc back in. If you're good with wood, possibly repair existing wood frame, but prob not worth it.

Of course, you could take the lot out and have a new upvc door and frame fitted.

 

which sounds like it was bodged in the past. Far far easier to rip the door and frame out and start again. either all upvc or all timber. If you decide to do this yourself, (which you could with timber but is harder with uPVC), come back and peeps will give you tips on frame/door fitting. Well within range of jobs a capable DIYer can do.

 

It is possible, just fiddly. If you really want to go down that route, see if you can get an offcut of hardwood from a timber yard, ask them to thickness it and put a chamfer on...basically tell them its a door step/cill. Easy enough to make in a machine shop. I had one made up many years ago to repair a bay window.

If you can get the old one out in one piece then you'll have a pattern for them to make it, otherwise measure to get basic dimensions. It doesn't have to be identical, just do the job

 

Matt, CGN just said get down to a timber yard and source a metre of hardwood. Anything will do. The present one is a softwood frame and was designed to last 20yrs. Years ago door cills/thresholds were made from Keruing(spelling). It's a tropical hardwood that is extremely hard wearing but I don't know where you can source it now.

Me, personally whole lot out and a grp door and frame in to replace it. Sound secure and looks good.