A proper door hinge installation sits flush in a clean mortise, aligns the knuckles, and swings without binding.
Whether you’re hanging a new slab or swapping a worn-out set, installing door hinges comes down to three phases: cutting accurate mortises, fastening the leaves, and hanging the door so it swings freely and latches cleanly. You don’t need a router for this job — a sharp chisel, a utility knife, and a drill are enough to get professional results on a standard wood door.
What You Need Before You Start
Gather the right tools first so the job goes smoothly. You’ll need a pencil, a combination square, a utility knife, a sharp wood chisel (about 1 inch wide), a hammer, a drill with the correct pilot-hole bit, and a screwdriver bit that matches your hinge screws. A torpedo level helps confirm the door is plumb before you fasten anything.
You’ll also need the hinges themselves. Standard residential doors typically use three hinges, but that count should match the door’s weight, size, and hardware specification — a solid-core door may need a fourth. Assa Abloy’s technical documentation notes that hinge styles and applications vary widely, and butt hinges, self-closing hinges, and specialty hinges each follow different installation details. For this guide, we’re covering standard butt hinges on a wood door.
Marking the Hinge Locations
Accurate marking prevents a misaligned door. For a standard passage door, a commonly cited placement is the top hinge about 5 inches from the top edge and the bottom hinge about 10 inches from the bottom edge, with a middle hinge centered between them. Measure carefully and mark both the door edge and the frame jamb using your combination square to keep the lines straight.
Hold the hinge leaf against the door edge and trace its outline with a sharp pencil. Do the same on the jamb. If you’re installing hinges on a pre-hung frame, the jamb mortises may already be routed — in that case, transfer those positions directly to the door edge instead of measuring fresh.
Cutting Mortises That Sit Flush
The mortise depth must match the hinge leaf thickness so the leaf sits flush with the door edge or jamb — nothing protrudes and nothing sits recessed. For standard-weight residential hinges, leaf thickness is typically 0.134 inch; heavy-weight hinges run about 0.180 inch. You’ll want the leaf surface level with the surrounding wood.
Work in this order for a clean cut:
- Score the outline with a utility knife, cutting through the wood fibers along your traced lines. This reduces tear-out and gives your chisel a clean edge to follow.
- Set the depth by marking the leaf thickness on the edge of the door, or use your chisel as a depth reference.
- Chisel out the mortise in shallow passes, working from the scored lines inward. Remove thin layers — about 1/16 inch at a time — rather than hacking deep cuts.
- Test-fit the leaf and remove any high spots until it sits perfectly flush.
If you’re installing on hollow metal doors, a different approach applies. Assa Abloy’s installation guidance for metal doors notes that self-tapping screws may be used and pilot holes aren’t needed for frame tapping, but a center punch improves accuracy by keeping the screw from wandering. For wood, always predrill pilot holes to prevent splitting — using a bit slightly smaller than the screw shaft.
Hanging the Door and Testing the Swing
With all three mortises cut, attach the leaves to the door edge and the jamb using the screws from your hardware kit. Don’t overtighten — stop when the screw head is flush and the hinge doesn’t flex.
Lifting the door into place is a two-person job. Have an assistant hold the door steady, or cushion it with an old towel and support it on its side while you work. Align the knuckles of the door-side and jamb-side leaves so the hinge pins slide through cleanly. Insert the pins from the top hinge first in sequence, then work your way down.
Test the swing by opening the door partway and letting it rest. A properly hung door should show no binding at any hinge, maintain an even reveal between the door and frame, and align the latch with the strike plate. If the door rubs or binds, loosen the affected hinge screws slightly, adjust the leaf position, and retighten. If the latch misses the strike, you may need to deepen or shift a mortise.
Hinge screws have fixed lengths for a reason. Assa Abloy’s patio-door installation document specifies fasteners such as #10 x 3/4 in. flat head screws for standard 2-knuckle hinge leaves and #8 x 1-1/4 in. flat head screws for the thicker side of certain hinge pockets — matching the fastener to the leaf keeps the hinge stable without risking damage to the door core.
If you’re still shopping for hardware before starting, our roundup of the best door hinges for any entryway compares weight ratings, finishes, and self-closing options to help you choose the right set for your door’s size and swing.
FAQs
How deep should a hinge mortise be?
A hinge mortise should be exactly as deep as the hinge leaf is thick, so the leaf sits perfectly flush with the surrounding wood surface. Standard residential hinge leaves run about 0.134 inch thick. If the mortise is too shallow the leaf protrudes and the door binds; too deep and the screws have less to bite into.
Can you install door hinges without a router?
Yes, a sharp chisel and a utility knife are all you need. Score the traced outline first to cut the wood fibers cleanly, then chisel out the mortise in shallow layers. Work from the scored lines inward and test-fit the leaf frequently until it sits flush. Go slow — removing too much wood at once is the most common mistake.
What screws do you use for metal door hinges?
For hollow metal doors, self-tapping screws work without pilot holes for frame tapping, though a center punch improves accuracy by keeping the screw from wandering. Match the screw length and head type to the hinge leaf — Assa Abloy specifies #10 x 3/4 inch flat head screws for standard 2-knuckle leaves and #8 x 1-1/4 inch flat head screws for certain thicker hinge pockets.
References & Sources
- Assa Abloy. “ANSI Door Hinges General Information.” Technical spec covering hinge leaf thicknesses, hinge counts, and installation parameters.