How to Properly Measure Your Door for a New Lockset Installation
Installing a new lockset is a great way to improve your home’s security and update your door’s appearance. Before purchasing a new lock, it’s essential to take accurate measurements to ensure a proper fit. In this guide, we’ll walk you through the key measurements you need and tips for a smooth installation.
Step 1: Gather Your Tools
Before you start measuring, have the following tools ready:
• Tape measure
• Pencil or marker
• Notepad for recording measurements
• Screwdriver (for removing the existing lock if needed)
Step 2: Measure the Door Thickness
Standard doors come in different thicknesses, and your lockset must be compatible with your door’s size.
How to Measure:
• Place the tape measure on the edge of the door.
• Measure from the interior surface to the exterior surface.
Standard Door Thickness:
• 1-3/8 inches – Common for interior doors.
• 1-3/4 inches – Standard for exterior doors.
• Other sizes – If your door is thicker or thinner than these, look for an adjustable lockset.
Step 3: Measure the Backset
The backset is the distance from the edge of the door to the center of the hole for the lockset.
How to Measure:
• Measure from the door edge to the center of the existing hole (or where the new lock will be installed).
Common Backset Sizes:
• 2-3/8 inches – Standard for most residential doors.
• 2-3/4 inches – Found on some exterior doors and commercial doors.
Most locksets are adjustable to accommodate both sizes, but it’s crucial to check before purchasing.
Step 4: Measure the Bore Hole Diameter
The bore hole is the round hole drilled into the door where the lock mechanism fits.
How to Measure:
• Place the tape measure across the hole’s widest point to find the diameter.
Common Bore Hole Sizes:
• 2-1/8 inches – Standard for most modern locksets.
• 1-1/2 inches – Found in older doors (may require an adapter or resizing).
Step 5: Measure the Strike Plate and Latch Hole
The latch hole is the small hole on the edge of the door where the latch inserts, and the strike plate is the metal plate mounted on the door frame.
How to Measure:
• Check the latch hole depth and width to ensure the new latch fits.
• Measure the strike plate size and screw hole spacing to see if it aligns with your existing setup.
If the new lock’s latch or strike plate is a different size, you may need to chisel or adjust the door frame for a proper fit.
Step 6: Check the Door Handing (For Handle Sets and Deadbolts)
Some locks and handles are designed specifically for left-hand or right-hand doors.
How to Determine Door Handing:
1. Stand outside the door (facing it as if entering).
2. If the hinges are on the left, it’s a left-hand door.
3. If the hinges are on the right, it’s a right-hand door.
For lever-style handles, make sure to buy the correct handing or a reversible handle if needed.
Final Tips Before Buying a New Lockset
✔ Double-check all measurements before purchasing to avoid mismatched hardware.
✔ Consider a smart lock or keyless entry if you’re upgrading for convenience.
✔ Match your lock’s finish to existing door hardware for a cohesive look.
✔ Ensure your lockset meets security standards, especially for exterior doors.
✔ Look for the BHMA Certified label for a rigorously tested lockset.
By following these steps, you’ll ensure a hassle-free lock installation with a perfect fit for your door.