Automatically-extendible deadbolt latch assembly

A latch assembly for a door including:

• a chassis;
• a latch bolt supported by the chassis and configured to move relative to the chassis between a retracted latch position and an extended latch position;
• an auxiliary bolt supported by the chassis and configured to move relative to the chassis between a retracted auxiliary position and an extended auxiliary position;
• a deadbolt supported by the chassis and configured to move relative to the chassis between a retracted deadbolt position and an extended deadbolt position, the deadbolt including a lower deadbolt leg having a catch;
• a guard lever having a free position and a secure position, wherein when the auxiliary bolt is in the extended auxiliary position the guard lever is in the free position allowing the latch bolt to move between the extended latch position and retracted latch position, and when both the auxiliary bolt is in the retracted auxiliary position and the latch bolt is in the extended latch position, the guard lever is in the secure position preventing movement of the latch bolt to the retracted latch position;
• and
• a sear connected to a top of the guard lever, the sear being configured to engage with the catch of the lower deadbolt leg when the guard lever is in the free position, thereby maintaining the deadbolt in the retracted deadbolt position, and the sear being configured to release from the catch of the lower deadbolt leg when the guard lever is in the secure position, thereby permitting the deadbolt to move to the extended deadbolt position.