Determining Bore Position

When ordering a pre-hung door, Sun Mountain provides complimentary machining (boring and mortising) to prepare the door for a handle or lockset. To ensure proper fit, confirm bore placement with your hardware supplier. If you purchase hardware from Sun Mountain, we’ll match it for you.

Bore Options

• Single Bore: Standard for interior doors. 
• Double Bore: Typically for exterior doors (lockset + deadbolt)

Standard Specifications 

• First Bore Height: Standard at 36” from the bottom of the door 
• Bore Diameter: 2-⅛”
• Double Bore Hole Spacing: 5-½” center-to-center
• Backset Options: Available in 2-⅜” and 2-¾”