How to Hang an Internal Door

Hanging an internal door is a satisfying carpentry task that most competent DIYers can tackle over a weekend. The work involves sizing the door leaf to the opening, cutting hinge and latch recesses, and adjusting until the door swings freely and closes cleanly. Rush the fitting and you’ll spend months fighting a door that sticks; take your time and it’ll last decades.

Standard UK Internal Door Sizes

Before buying a door, measure the opening width and height precisely. UK internal doors come in a range of standard sizes, but openings in older properties often vary.

Building Regulations Part M (access) require a minimum clear opening width of 750 mm for new or replacement doors in habitable rooms, plan for a door leaf of at least 826 mm to achieve this once the frame is accounted for.¹

Leave a 2–3 mm clearance gap on each side and the top, and 6–8 mm at the bottom (more if carpeted).

Tools and Materials

• Tape measure, pencil, combination square
• Workbench or door horses
• Circular saw or hand saw
• Plane (bench plane and block plane)
• Chisel set (25 mm and 12 mm) and mallet
• Power drill and 25 mm Forstner bit or flat bit
• 65 mm or 75 mm butt hinges (× 3 for full-height doors)
• Tubular latch and handles
• Sandpaper (80 and 120 grit)
• Wood primer and paint, or finishing oil if solid oak

Step 1: Measure and Trim the Door

Offer the door to the opening and mark where it needs to be trimmed. Most modern hollow-core and solid doors have a 12 mm lipping on each edge and 20–30 mm top and bottom rails, which gives you scope to remove material without breaking into the core.

• Width: trim equally from both sides if possible to keep the lipping even.
• Height: trim from the bottom to preserve the top rail.

Use a sharp circular saw with a fine-tooth blade and a guide rail to keep cuts straight. Score the face with a utility knife first to prevent tearout on veneered or painted doors. After sawing, clean the edges with a bench plane.

Step 2: Mark the Hinge Positions

The standard positions are:

• Top hinge: 150 mm down from the top of the door.
• Bottom hinge: 225 mm up from the bottom.
• Middle hinge (doors over 1,981 mm or heavy solid doors): centred between the other two.

Mark these positions on the door edge and transfer them to the frame. Use a combination square to ensure both sets of marks align.

Step 3: Cut the Hinge Recesses

Hinge recesses (also called hinge housings or gains) must be cut accurately, too deep and the door will bind; too shallow and it won’t close flush.

1. Hold the hinge on the mark and score around it with a sharp chisel or knife.
2. Set your chisel to the hinge thickness (usually 2–2.5 mm) and make a series of cuts across the grain within the scored lines.
3. Pare out the waste horizontally, working back to your depth line.
4. Test-fit the hinge: it should sit perfectly flush with the door edge and frame face.

Step 4: Fix the Hinges and Hang the Door

Screw one leaf of each hinge to the door edge using the supplied screws. Start the screws at a slight angle toward the frame side, this pulls the hinge tight into the recess as you drive them home.

Prop the door in the opening at the correct height using timber wedges under the bottom edge, align the other hinge leaf to the frame recesses, and screw them in. Start with one screw per hinge, check the door swings and closes correctly, then insert all remaining screws.

If the door drags at the latch side (called “hinging” or “binding on the latch”), the hinges may be set too deep, pack them out with a strip of cardboard. If it springs open, the recesses are too shallow, deepen them by a fraction.

Step 5: Fit the Latch and Handles

Most internal doors use a 63 mm or 76 mm tubular latch:

1. Mark the centre height of the handle, typically 990–1,000 mm from the floor, which suits most adults and children.
2. Drill a 25 mm hole through the door face for the spindle (the square bar that operates the latch).
3. Mark and drill the 22 mm hole in the door edge for the latch body.
4. Chisel a recess for the latch faceplate, it should sit flush with the edge.
5. Fit the keep (strike plate) on the frame so the latch bolt engages cleanly; chisel a housing for the bolt.

Test the latch by closing the door and checking it catches first time without rattling.

Adjusting a Door That Sticks or Binds

Even a well-hung door can shift as the house settles or humidity changes. Common issues:

Fire Doors: Important Differences

If you are replacing a fire door, between a garage and the house, in an HMO, or as required by Building Regs Part B, you must use a certified FD30 or FD60 door leaf fitted with:

• Three 75 mm fire-rated steel hinges with intumescent strips
• An intumescent and smoke seal around all four edges of the frame
• A fire-rated closer if required

Standard hollow-core doors are not acceptable as fire doors. Check your Building Regs requirements before ordering.

Cost Summary

A carpenter can typically hang two to three doors per day, making professional fitting cost-effective if you have multiple doors to do throughout a house.