Lock Installation & Repair Flashcards

What is the standard thickness of a residential exterior door?

Answer: 1-3/4 inches

Exterior residential doors are typically 1-3/4 inches thick; interior ones are often 1-3/8.

How many hinges are typically used on a standard 80-inch door?

Answer: 3

Three hinges is the standard for a 7-foot door; heavy doors may need four.

Why might a code officer object to a double-cylinder deadbolt in a residence?

Answer: It requires a key to exit, impeding fire egress

Keyed-both-sides locks can trap occupants during emergencies, so many codes restrict them.

Which tool is used to cut the 2-1/8 inch cross bore in a door?

Answer: Hole saw

A 2-1/8" hole saw cuts the face bore for cylindrical locks, usually using a jig.

A master key system commonly uses what in the pin stack?

Answer: Master wafers or master pins creating a second shear line

Additional pins create two shear lines so two keys open the same lock.

Before installing a smart deadbolt, which measurement should be verified first?

Answer: Door thickness and backset

Smart locks fit specific thickness ranges and backsets that must match the door prep.

What does a door reinforcer or edge wrap primarily protect?

Answer: The area around the lock bore from splitting when kicked

It strengthens the weakened wood around the lock bores against splitting.