Abstract: A door frame having a hinged jamb, a strike jamb and a header, each of which is in two parts. One part of each pair has a channel for slidably receiving a lipped segment of the other part. A lipped cover on the first part engages the lipped segment of the second part to limit movement of the two parts relative to one another. A biasing means on the first part urges the two parts against one another. The biasing means is rigidly affixed to the first part and extends across the channel to leave a small gap through which the lipped segment of the first part can be rotatably inserted.