Has there been a mistake (door hanging),can it be fixed?

chappers

As leveller says it looks like the structural openings have been set out for frames rather than linings. not the end of the world, if the gap is 50mm then foam in the gap and fit 68mm architrave. I suspect your builder already has this covered.

Saver-upper

Thank you everyone for taking the time to post.
So,last night I managed to get through to the builder.He said that yes,there had been a mistake,and it was fixable.
By the time I got home about 30 minutes ago,he had been in and all doors have been "fixed" (not the technical term,I know,but the spaces above all 3 doors have been "filled in"(with what,I don't know,sorry),and plastered over.
He did try to explain on the phone how the mistake had happened ,but to be honest,I just wanted to hear the reassurance that it was fixable.This extension is huge(kitchen,bedroom,garage,small bathroom),has taken since September,we have been out of the house since Christmas Eve,and I just wanted to know that there were no major setbacks at this end of the game.
I thought the mistake might have been something to do with door spaces being measured before screeding was done,but that didn't make sense.Now,looking at it,the door going into the garage,you actually "step up" slightly before steping down into garage,so that door hung a bit higher,anddidn't need to be "fixed".It looks like they may have then made the spaces for the other 3 internal doors at the same height,forgetting that they are all on a lower, flat floor.
I don't know,really.But very pleased it is fixed.
Thanks again for everyone's advice .

Wassa123

Those gaps are quite common around here.

Granted only in the ~1950s-1970 houses. Think they were for ventilation before the vents in the windows came into existence.

chappers

Saver-upper wrote: »

Now,looking at it,the door going into the garage,you actually "step up" slightly before steping down into garage,so that door hung a bit higher,anddidn't need to be "fixed".It looks like they may have then made the spaces for the other 3 internal doors at the same height,forgetting that they are all on a lower, flat floor.

That's exactly what has happened they have , as said allowed for a frame as is on the garage door whereas the others have linings and architraves.