What size hole saw do I need for a deadbolt?

The size of the hole saw needed for a deadbolt installation depends on the specific deadbolt you are using and the manufacturer's recommendations. Deadbolts typically require two holes: one for the lock cylinder and one for the latch or bolt. I'll provide a general guideline for the most common sizes, but it's important to consult the instructions provided by the deadbolt manufacturer for precise measurements.

1. Lock Cylinder Hole: The lock cylinder is the part of the deadbolt where the key is inserted. It requires a hole of a specific diameter to accommodate it. The most common size for a lock cylinder hole is 2-1/8 inches (54 mm) in diameter. This is the standard size used for most residential deadbolts. However, it's essential to verify the lock cylinder size recommended by the manufacturer of your specific deadbolt.
2. Latch/Bolt Hole: The latch or bolt is the part of the deadbolt that extends into the door jamb, keeping the door secure. The hole for the latch is typically smaller than the lock cylinder hole. The standard size for a latch hole is 1 inch (25 mm) in diameter. This allows sufficient space for the latch to operate smoothly. Again, it is crucial to refer to the manufacturer's instructions for the exact size required.
When drilling the holes for the deadbolt, it's recommended to use a hole saw specifically designed for cutting holes in doors. These hole saws have a pilot drill bit in the center to guide the cutting action and typically attach to a drill or hole saw arbor. Ensure that the hole saw you choose matches the diameter required for the lock cylinder and latch holes.

It's worth noting that these sizes are common for residential deadbolts, but commercial or specialized deadbolts may have different size requirements. To ensure accuracy and compatibility, always refer to the instructions and specifications provided by the deadbolt manufacturer. If in doubt, consult a professional locksmith or contractor who can assist you in selecting the appropriate size hole saw for your specific deadbolt installation.