If this is an attic scuttle measure an inch in from all four corners.
How to close door for attic.
Measure 1 inch in from the corners of the attic hatch on the frame on the opposite side where the hinges have been mounted.
Weatherstrip the edges and put a piece of rigid foam board insulation on the back of the door.
Shut the attic door once you and your partner are in the attic.
Inspect the brackets at the door hinge where the springs attach to the attic door frame.
If you have pull down attic stairs or an attic door these should be sealed in a similar manner.
Cut a piece of fiberglass or rigid foam board insulation the same size as the attic hatch and nail or glue it to the back of the hatch.
Weatherstrip the attic access hatch or door.