How to Hang a New Internal Door in an Old Frame
Back to Doors, Windows & Fixings Project Guides

Replacing an internal door sounds simple until the frame tells the truth. Older frames are often slightly twisted, out of square, painted over many times or worn around the hinge positions. The safest route is to measure carefully, trim slowly and keep checking the actual opening.
Tools
- Tape measure, pencil, masking tape and straight edge
- Long level, square, wedges and clamps
- Plane, sharp chisels and mallet
- Drill, pilot bits and screwdriver bits
- Saw with guide if larger trimming is needed
Materials
- Internal door sized for the opening
- Hinges, screws, handle and latch set
- Wood filler for old fixing holes if needed
- Primer, paint or sealant for cut edges
- Dust sheet and small timber offcuts for supports
1. Measure the Opening Before Cutting

Measure the opening at the top, middle and bottom, then measure both sides for height. Check the frame with a long level and mark the hinge side and latch side on the door. Do not assume the frame is square, especially in older houses.
- Use the old door only as a rough reference.
- Check floor clearance for carpet, thresholds and door swing.
- Mark cut lines lightly and clearly before removing any timber.
2. Trim Slowly and Test Fit Often

Trim small amounts at a time, then offer the door back into the opening with wedges underneath. Aim for even practical gaps rather than a perfect theoretical measurement. It is much easier to remove a little more timber than to repair a cut that went too far.
3. Mark and Cut the Hinge Recesses

Transfer hinge positions from the frame to the door. Score around each hinge leaf with a sharp blade, then chisel gradually so the hinge sits flush. Drill pilot holes before fitting screws to reduce splitting and make adjustment easier.
4. Hang the Door, Then Fit the Latch

Hang the door on the hinges and check the swing before fitting the latch and handle. If the door rubs, mark the contact point with pencil and remove only a small amount. Once the fit is right, seal or paint any freshly cut timber edges so they do not absorb moisture unevenly.
Open the checklist builder | Estimate fixings | Plan the budget