Door Jamb advice needed – PLEASE HELP!!!

They are probably "split Jambs" Installing Split-Jamb Interior Doors | Home Depot Canada

 

RU above is on the money - they are a split jamb which is a pre-hung door system. The installer just needs to pack the jamb (not jam) plumb and there is no need for checking out hinges, latches or strikes. The hinges will have rounded corners instead of square as they are done by a router which can only do round corners.

There has been a lot of misinformation in the posts above. If you are new to DIY then hanging a door is probably not the place to start as you will probably be disappointed with your result. If however you want to have a crack yourself then you really need to pull out the existing and start again. You could probably reuse the hinge jamb to save you the trouble of checking out the hinges. Nail the jamb together (2 stiles and a head) then put it in to the opening. Put packers behind the hinge jamb first and ensure it is plumb then hang the door on that jamb. Use the door as a guide for packing and fixing the other side to the stud. You are going to have to check in your striker and I would get a replacement which is square rather than round as this will be difficult for you to check in neatly. Then replace the door stops, architraves which will need to me mitred, paint and you are good to go.

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Been hiding in the woodwork @Tools?

 

No, just sitting in the peanut gallery...

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