How to Hang an Internal Door: Step-by-Step DIY Guide

Hanging a door is one of those jobs that seems like it should be straightforward. It’s a flat piece of wood that goes in a rectangular hole — how hard can it be? The answer, as I discovered when I hung my first door, is: harder than you think, but absolutely doable once you understand the process.

The difference between a door that swings smoothly, latches perfectly, and has even gaps all the way around versus one that sticks, scrapes, and won’t close properly comes down to careful measuring and patient fitting. This guide takes you through every step, from measuring the opening to adjusting the final close.

Measuring Your Door Opening

Before you buy a door or start any work, you need accurate measurements of your door opening. And here’s the first thing to know: door openings in older houses are almost never perfectly square or consistent. My 1870s place has openings that vary by up to 10mm from top to bottom — and that’s actually not bad for a Victorian house.

Measure the following:

• Width — measure at the top, middle, and bottom of the frame opening. Record the smallest measurement.
• Height — measure on the hinge side and the latch side of the frame. Record the smallest measurement.
• Depth of the frame rebate — this is the step in the door frame where the door sits when closed. Standard internal doors are 35mm thick, and most frames have a rebate to match.

Required gaps:

So if your frame opening is 762mm wide, your door needs to be approximately 756mm wide (762mm minus 3mm gap each side). Most standard internal doors come in set sizes (610mm, 686mm, 726mm, 762mm, 838mm wide), so you’ll almost certainly need to trim the door to fit.

Choosing the Right Door

Hollow Core vs Solid Core

Internal doors come in two basic constructions, and the difference matters more than most people realise:

Hollow core doors have a cardboard honeycomb interior between two thin skins. They’re light (around 8-10 kg), cheap (£25-50), and easy to handle. For bedrooms and living spaces where you don’t need sound insulation, they’re perfectly adequate.

Solid core doors have a dense interior — either solid timber, particleboard, or an engineered core. They’re heavier (15-25 kg), more expensive (£60-150+), but significantly better for sound insulation and they feel much more substantial. For bathrooms, bedrooms where privacy matters, and in period properties where you want a quality feel, solid core is the way to go.

A practical note: If you’re trimming more than about 10mm off a hollow core door, you may cut past the solid edge banding and into the hollow centre. Check the manufacturer’s trim allowance — most hollow core doors can only lose 5-10mm per edge before you hit the void.

Tools You’ll Need

Hanging a door requires a specific set of tools. Missing any of these will make the job significantly harder:

• Tape measure and pencil
• Hand plane or electric planer — for trimming the door to size
• A sharp chisel (25mm/1-inch is the most useful size) — for cutting hinge recesses
• A mallet — for driving the chisel
• A cordless drill/driver — for hinge screws and handle fitting
• A hole saw or spade bit (usually 25mm for latch holes) — for drilling the handle mechanism hole
• A combination square — for marking hinge positions accurately
• Screwdriver — for final adjustments
• Wedges or shims — for holding the door in position during fitting
• A spirit level — for checking the door hangs plumb
• Sandpaper (120-grit) — for smoothing trimmed edges

Step 1 — Trim the Door to Size

How to Plane a Door

Unless you’re extremely lucky, your new door won’t fit the frame perfectly. You’ll need to trim it, and the best tool for this is a hand plane (for fine adjustments) or an electric planer (for removing more material quickly).

The process:

1. Hold the door in the frame opening using wedges under the bottom to set the correct top gap. Mark where the door needs trimming with a pencil line — keep the marks on the waste side.
2. Remove the door and lay it on its edge on a stable surface. A workbench is ideal; alternatively, wedge it between your legs while you plane (this is the traditional method and works fine with practice).
3. Plane in the direction of the grain, never against it. If you’re planing across the top or bottom edge, plane from the outside edges toward the centre to avoid splitting the corners.
4. Take thin passes — about 0.5mm at a time. It’s far easier to remove a little more than to add back wood you’ve taken off.
5. Keep checking the fit in the frame as you go. You want even gaps all around.

For trimming the bottom: If you need to remove more than about 5mm from the bottom, a circular saw with a straight-edge guide gives a cleaner, faster result than planing. Score the cut line with a knife first to prevent splintering on the face side.

Getting the Gap Right

The most common mistake is trimming too much off one side. Take your time and check frequently. A 2p coin is roughly 2mm thick — useful as a quick gap gauge. Hold the door in position with wedges, check the gap with a coin, and mark any spots that still need material removed.

Once you’re happy with the fit, lightly sand all trimmed edges with 120-grit sandpaper to remove any roughness and slightly round the sharp corners.

Step 2 — Mark and Cut Hinge Recesses

Internal doors use two or three hinges. Two hinges are standard for lightweight hollow core doors; three hinges are recommended for solid core doors or any door that feels heavy.

Hinge positions:

• Top hinge: 150mm from the top of the door to the top of the hinge
• Bottom hinge: 225mm from the bottom of the door to the bottom of the hinge
• Middle hinge (if using three): Centred between the top and bottom hinges

If you’re replacing an existing door and the frame already has hinge recesses cut, match your new door’s hinge positions to the existing recesses. This saves you cutting new recesses in the frame.

Using a Chisel

This is the traditional method and gives excellent results once you’ve practised it a couple of times:

1. Hold the hinge in position on the edge of the door at your marked position. Draw around it with a sharp pencil or marking knife.
2. Set a marking gauge to the thickness of the hinge leaf (usually about 2-2.5mm) and score a line along the face of the door to set the recess depth.
3. With the chisel held vertically, tap along the outline of the hinge to cut the fibres. Don’t go deeper than your depth line.
4. Make a series of parallel chisel cuts across the recess, about 3-4mm apart, down to your depth line.
5. Now hold the chisel flat (bevel up) and pare out the waste from the side. The parallel cuts you made will break away in neat chips.
6. Test the hinge in the recess — it should sit flush with the door edge. If it’s proud (sticking out), pare a little more. If it’s too deep, pack it with a thin piece of card behind the hinge.

Using a Router (Faster Method)

If you have a router, a hinge jig and straight-cutting bit makes this much faster and more consistent. Clamp the jig to the door at the marked position, set the cutting depth to match the hinge leaf thickness, and rout out the recess. It takes about 30 seconds per hinge versus 5-10 minutes with a chisel.

If you’re hanging multiple doors (a whole house renovation, for example), a router and hinge jig will save you hours. For a single door, a chisel is perfectly fine.

Step 3 — Hang the Door on the Hinges

With the hinge recesses cut in both the door and the frame (if the frame doesn’t already have them):

1. Screw the hinges to the door first. Use the screws provided with the hinges. Pre-drill pilot holes to prevent splitting — a 2mm drill bit for most hinge screws.
2. Have a helper hold the door in position in the frame, or use wedges under the bottom to get the correct height.
3. Align the hinge leaves with the recesses in the frame.
4. Drive one screw into each hinge first — don’t fully tighten yet. This lets you check the swing and alignment before committing.
5. Open and close the door. Check the gaps are even all around. If the door catches anywhere, you may need to adjust the hinge recess depth.
6. Once you’re happy with the alignment, drive all remaining screws and tighten fully.

Tip: If the door tends to swing open or closed on its own, the frame isn’t perfectly plumb. This is common in older houses. You can fix it by slightly deepening one side of a hinge recess to shift the door’s hang, but for most internal doors, a door stop or magnetic catch is the easier solution.

Step 4 — Fit the Handle and Latch

With the door hung and swinging freely, it’s time to fit the handle set.

1. Mark the handle height: Standard handle height is 1000mm from the floor to the centre of the handle. Match existing doors in the house for consistency — there’s nothing worse than handles at different heights on the same landing.
2. Drill the handle spindle hole: Most handle sets need a 20mm hole drilled through the face of the door for the spindle. Use a flat/spade bit and drill from both sides, meeting in the middle, to avoid blowout on the far side.
3. Drill the latch hole: Drill into the edge of the door (usually a 25mm hole) for the latch mechanism. The depth should match your latch length — typically 64mm or 76mm.
4. Cut the latch faceplate recess: Using the same chisel technique as the hinges, cut a shallow recess for the latch faceplate so it sits flush with the door edge.
5. Insert the latch, screw on the faceplate, attach both handles, and test the mechanism.
6. Mark and cut the strike plate recess in the frame where the latch bolt engages. Close the door, mark where the latch contacts the frame, chisel the recess, and screw the strike plate in place.

Step 5 — Adjust for a Perfect Close

Your door is hung and the handle works, but chances are it needs fine-tuning. Here’s how to fix the most common issues:

Door doesn’t latch: The latch bolt isn’t aligning with the strike plate. Adjust the strike plate position — you usually only need to move it a millimetre or two. A file can enlarge the strike plate opening slightly.

Door rubs at the top corner on the latch side (“binding”): The top hinge recess may be too deep. Place a thin piece of card behind the hinge to pack it out slightly. Alternatively, the bottom hinge might need deepening to pull the bottom of the door closer to the frame.

Door rattles when closed: The door isn’t sitting snugly against the door stop. Adjust the door stop (if it’s a pinned-on stop rather than part of the frame) by tapping it inward with a hammer and a block of wood.

Door scrapes on the floor: If it’s catching on carpet, you may need to remove the door and plane a little more off the bottom. For solid floors, check whether the floor is uneven rather than the door being too long.

Dealing with Frames That Aren’t Square

In older houses, door frames can be out of square by several millimetres. The frame might lean, the head might not be level, or the sides might not be parallel. Here’s how to cope:

• Scribe the door to the frame: Rather than trimming to straight lines, hold the door in position and use a pencil or scribing tool to trace the frame’s irregularities onto the door. Then plane to the scribed line. The door will have slightly tapered or curved edges, but the gaps will be consistent.
• Pack the hinges: If the frame leans, you can compensate by packing one hinge deeper or shallower than the other. Thin cardboard shims behind the hinge leaf adjust the door’s position.
• Accept imperfection: In a genuinely wonky frame, aim for consistent gaps rather than perfect gaps. A 3mm gap that’s even all around looks far better than a 2mm gap on one side and 5mm on the other.

Recommended Door Hanging Tools

Here’s my recommended kit for hanging internal doors:

Essential tools:

• A No. 4 or No. 5 hand plane — the single most important tool for door fitting. A sharp plane makes this job genuinely enjoyable; a blunt one makes it miserable.
• A 25mm bevel-edge chisel — for hinge and latch recesses. Get a decent one and keep it sharp.
• A wooden mallet — for driving the chisel. Never hit a chisel with a hammer unless it has a steel cap.
• A cordless drill/driver with a set of spade bits
• A combination square and marking gauge
• Wooden wedges — for holding the door in position during fitting

Nice-to-have upgrades:

• A hinge jig and router bit — saves significant time if you’re hanging multiple doors
• An electric planer — for removing larger amounts of material quickly
• A door lifter (foot-operated lever) — holds the door at the correct height while you screw the hinges, eliminating the need for a helper

Hardware:

• 75mm or 100mm butt hinges (three per door for solid core, two for hollow core) — stainless steel or zinc-plated
• Door handle set with latch — lever on rose is the most common internal door style
• A door stop — either a floor-mounted or wall-mounted type to prevent the handle hitting the wall

Hanging a door is one of the most satisfying DIY jobs there is. When you close that door for the first time and it clicks shut perfectly with even gaps all around, you’ll feel like a proper tradesperson. Just don’t be discouraged if the first one takes you three hours — by the fourth or fifth door, you’ll have it down to under an hour.