Replacing a door slab (the door panel without the frame or hardware pre-cut) is a practical and cost-effective way to update a home’s interior or exterior. This project allows the existing door frame, or jamb, to remain in place, saving considerable time and avoiding extensive trim work. The process requires precision in transferring measurements and cutting the new door to fit the established opening and hardware locations. Successfully hanging the new door relies on accurately matching the dimensions and hardware placement of the old door to the new one.
Preparation and Sizing the New Door Slab
The first step involves safely removing the old door from its frame by tapping out the hinge pins, starting with the bottom hinge. Once removed, inspect the existing frame to ensure it is plumb, square, and free of damage, as the new door’s fit depends on the frame’s integrity.
Accurate sizing of the new door slab is the foundation of the installation, and the old door serves as the most reliable template. Place the old and new doors side-by-side or stacked, aligning the top edge and the hinge side perfectly flush. This alignment allows for precise marking of the new door’s height and width, accounting for necessary clearance gaps.
The new door must be trimmed to allow for a consistent gap, or reveal, of approximately 1/8 inch around the top and sides when closed. This uniform space prevents the door from binding due to seasonal expansion and contraction. Trimming is best accomplished using a circular saw guided by a straight edge clamped to the door. For final, precise adjustments, a sharp hand plane can be used to shave small amounts of material from the edges.
Transferring and Cutting Hinge Mortises
With the new door slab sized correctly, create the recesses for the hinges, known as mortises, so they align perfectly with those cut into the door frame. Transfer the exact hinge locations from the old door to the new slab by aligning the two doors flush at the top and hinge side. Use a square to mark the top and bottom of each hinge location onto the new door’s edge.
Once the outlines are marked, establish the depth of the mortise, which must match the thickness of the hinge leaf so the hinge sits flush with the door’s edge. Use a utility knife to score the outline of the mortise, cutting the wood fibers to prevent tear-out. A sharp chisel and hammer are then used to carefully remove the wood within the scored area, working from the edges inward to the correct depth.
The mortise depth is correct when the hinge leaf rests in the recess without protruding or sinking below the surface. After the mortises are cut, temporarily screw the hinges into place. Pilot holes must be drilled for the screws before final installation, which prevents the wood from splitting and ensures the screws hold securely.
Boring Holes for the Lockset and Latch
Installing the door handle and latch mechanism requires boring two distinct holes: a large cross-bore hole for the handle spindle and a smaller edge-bore hole for the latch mechanism. The location is determined by the backset, the distance from the door’s edge to the center of the handle hole (typically 2-3/8 inches or 2-3/4 inches). Use a lockset template to accurately mark the center points for both holes.
The main handle hole is drilled using a 2-1/8 inch hole saw, the standard diameter for most residential locksets. To prevent splintering on the opposite side of the door, drill only until the pilot bit pokes through the far side. Complete the drilling by reversing the process, drilling from the opposite side to meet the initial cut.
The latch hole, which runs from the door’s edge into the cross-bore, is typically drilled with a 1-inch spade bit or hole saw. Insert the latch mechanism and trace its faceplate onto the door edge. A shallow mortise is then carefully chiseled out to the depth of the latch plate, ensuring the plate sits flush with the door’s edge for proper latch function.
Final Hanging, Testing, and Adjustment
With all necessary cuts and bores completed, permanently attach the hinges to the new door slab. Position the door in the frame, aligning the hinge leaves on the door with the corresponding leaves on the jamb. A wedge or block placed under the door can help support its weight and align the hinges.
The final step involves inserting the hinge pins, starting with the top hinge, to connect the door to the frame. Once the pins are in place, test the door by swinging it open and closed to check for smooth operation and proper latching. Visually inspect the reveal (the gap between the door and the frame) to ensure it is consistent on all sides.
If the door sticks or the reveal is too tight, a small amount of material can be removed with a hand plane. If the door does not latch correctly, the strike plate on the jamb may need adjustment. Minor adjustments to the reveal can also be made by tightening or loosening the screws on the hinges, or by placing a thin shim behind a hinge leaf to subtly push the door in or out of the frame.