Hanging an interior door plumb and level is one of those jobs that looks straightforward but rewards careful preparation. Get it right and the door swings smoothly, latches cleanly, and looks great for years. Rush it, and you'll be planing, shimming, and adjusting indefinitely. Here's how to do it properly.
Tools and Materials You'll Need
Before you start, gather everything so you're not hunting around mid-job:
- Spirit level (at least 600 mm, ideally 1200 mm)
- Tape measure
- Combination square
- Pencil
- Hand plane or power planer
- Chisel set and mallet
- Cordless drill/driver
- Hammer
- Wedges or timber shims
- Timber packers
- 75 mm and 50 mm screws
- Door hinges (typically 3 × 100 mm butt hinges for a standard interior door)
- Door latch/handle set
- Safety glasses and hearing protection
Check the Frame First
Before touching the door, check the door frame (lining and jamb). Use your spirit level to confirm the head jamb is level and both side jambs are plumb. In older NZ homes — especially villas and bungalows — frames can rack and twist over time. If the frame is significantly out, you may need to pack or refit it before hanging the door. A frame that's more than 3–4 mm out of plumb over its height will cause ongoing problems.
Also check the floor level across the door opening. If the floor slopes, you'll need to account for this when setting your door bottom clearance.
Size the Door to the Opening
A standard interior door in NZ is typically 2040 mm × 820 mm × 40 mm, but openings vary. You need a consistent gap around the door:
| Location | Recommended Gap |
|---|---|
| Top (head) | 2–3 mm |
| Latch side | 2–3 mm |
| Hinge side | 2–3 mm |
| Bottom (over carpet) | 10–15 mm |
| Bottom (over hard floor) | 5–8 mm |
Mark the door carefully before cutting. Use a hand plane or power planer to trim the edges — always plane from the ends inward on the top and bottom to avoid splitting the timber. If you're removing more than about 5 mm, a power planer saves time, but finish with a hand plane for a clean, straight edge.
Mark and Cut the Hinge Recesses
For a standard interior door, fit three hinges: one 200 mm from the top, one 200 mm from the bottom, and one centred between them. Three hinges are recommended over two for better support and to reduce warping — this aligns with good practice under NZS 3604 framing principles for door assemblies.
- Hold the door in the opening using wedges to maintain your gaps, and mark hinge positions on both the door edge and the jamb simultaneously — this ensures they line up perfectly.
- Use a sharp chisel to cut the hinge recess (mortise) to the exact depth of the hinge leaf. The hinge face should sit flush with the timber surface — not proud, not recessed too deep.
- Test-fit each hinge before screwing off.
Hang the Door
- Screw the hinges to the door first, then offer the door up into the frame. Use wedges under the door to hold it at the correct height while you work.
- Screw the top hinge to the jamb first with one screw, then check the door swings freely and the gaps are consistent. Adjust with shims behind the hinge if needed.
- Once happy, fit all screws. Use at least one 75 mm screw per hinge into the structural framing (not just the lining) — this is especially important on the top hinge, which takes the most load.
- Check the door swings fully open and closed without binding, and that it stays in any position you leave it (neither swinging open nor closed on its own).
Fit the Latch and Strike Plate
With the door hanging correctly, mark and bore the latch hole using a hole saw (typically 54 mm diameter) and the latch bolt hole on the door edge. Chisel the latch faceplate recess flush. Close the door gently to mark the strike plate position on the jamb, then chisel the recess and fit the strike plate. The latch should engage smoothly without lifting or forcing.
Common Mistakes to Avoid
- Not checking the frame before starting — always plumb and level the frame first
- Hinge recesses too deep — causes the door to bind on the latch side
- Using screws that are too short — hinges can pull out under load
- Ignoring floor slope — leads to uneven bottom gaps
- Rushing the planing — take light passes and check frequently
When to Call a Professional
Hanging a door is generally not restricted work under NZ building law, so a competent homeowner can tackle it. However, consider calling a qualified joiner if:
- The frame itself needs rebuilding or significant repair
- You're fitting a fire door (these have specific requirements under the NZ Building Code)
- The job involves structural alterations to the opening, which may require a building consent — always check with your local council
- You're not confident with hand tools and risk damaging an expensive door
A skilled joiner will have the door hanging perfectly in a fraction of the time. You can find qualified local joiners on tradedirectory.co.nz.
Sources & Further Reading
- MBIE Building Performance – NZ Building Code
- Standards New Zealand – NZS 3604 and related standards
- BRANZ – Building Research Association of NZ
- Bunnings NZ – Door hanging tools and hardware
- Mitre 10 NZ – Interior doors and joinery supplies
- Licensed Building Practitioners – Find a qualified tradesperson
