French doors will not close fix
A single misaligned French door can increase your heating bill by up to £120 a year through draughts, according to the Energy Saving Trust (Energy Saving Trust, 2026). The fix is often straightforward and costs nothing if you have basic tools. This guide explains the three most common causes and how to fix each one yourself, plus when to call a tradesperson or a structural engineer.
Fixing French doors that won't close can save up to £120 a year on heating bills. The most common fix is tightening hinge screws, which costs nothing if you have a screwdriver. Check for sagging with a 30-second gap test before calling a tradesperson.
- A misaligned French door can cost up to £120 a year in draughts.
- Check for sagging with a 30-second gap, level, or latch test.
- Tightening hinge screws costs nothing if you have a screwdriver.
- Planing the door edge is a zero-cost DIY fix with a plane.
- Replace worn hinges for £10-£30 to stop the door shifting.
- French doors will not close fix
- The three most common reasons French doors will not close
- How to check for a sagging door in 30 seconds
- Quick numbers — costs and savings for fixing a misaligned French door
- The direct fix — adjust the hinges to realign the door
- When to plane the door edge instead of adjusting hinges
- How to verify an installer if DIY is not an option
- When a misaligned door signals a bigger problem
The three most common reasons French doors will not close
Sagging. The door’s weight pulls the hinge side down, causing the latch side to drop and catch on the frame. This is most common in older, heavy wooden doors. Expansion or contraction. Changes in temperature and humidity cause timber doors to swell in summer and shrink in winter, altering the gap between door and frame. Loose or worn hinges. Over time, hinge screws can work loose, or the hinge pin can wear, allowing the door to shift out of alignment (Energy Saving Trust, 2026).
How to check for a sagging door in 30 seconds
The gap test. Open the door halfway and look at the gap between the top of the door and the frame. A larger gap at the top than at the bottom indicates sagging. The level test. Place a spirit level vertically against the latch side of the closed door. If the bubble is not centred, the door is not plumb. The latch test. Gently push the door closed. If you need to lift the handle to get the latch to engage, the door is sagging (NHBC Standards, Chapter 6, 2026).
Quick numbers — costs and savings for fixing a misaligned French door
| Fix type | Typical DIY cost (GBP) | Typical tradesperson cost (GBP) | Estimated annual energy saving (GBP) |
|---|---|---|---|
| Tighten hinge screws | £0 (if you have a screwdriver) | £50–£80 (call-out) | Up to £120 |
| Adjust hinge pins or add shims | £5–£15 (shims) | £80–£150 | Up to £120 |
| Plane the door edge | £0 (if you have a plane) | £100–£200 | Up to £120 |
| Replace worn hinges | £10–£30 (hinges) | £100–£180 | Up to £120 |
Source for savings: Energy Saving Trust, 2026. Source for typical trade costs: Checkatrade, “Average costs for door repairs” (2026).
The direct fix — adjust the hinges to realign the door
For a sagging door. Tighten the top hinge screws first. If the screw holes are stripped, remove the screw, insert a matchstick or wooden toothpick coated in wood glue, reinsert the screw, and tighten. For a door that is too tight at the top. Loosen the top hinge screws slightly, place a thin shim (e.g., a piece of cardboard) between the hinge leaf and the door jamb, then retighten. This pushes the door away from the frame at the top. For a door that is too tight at the bottom. Loosen the bottom hinge screws, add a shim behind the hinge leaf, and retighten (NHBC Standards, Chapter 6, 2026).
When to plane the door edge instead of adjusting hinges
When the gap is even but the door is too wide. If the door is binding on the latch side all the way down, the door has swollen or was fitted too tightly. Planing is the solution. How to check. Close the door and run a piece of paper between the door edge and the frame. If the paper is hard to slide at any point, the door is too wide. The fix. Remove the door, mark the binding area with a pencil, and plane the latch-side edge. Take off no more than 1–2 mm at a time and test-fit frequently (Wood Window Alliance, 2026).
How to draught-proof your home on a budget
How to verify an installer if DIY is not an option
Check MCS certification. Any installer fitting replacement doors under a grant or energy-efficiency scheme must be MCS-certified (MCS, 2026). Check TrustMark registration. For all home improvement work, TrustMark-registered tradespeople are vetted and insured (GOV.UK, 2026). Check FENSA or CERTASS. For replacement doors that are part of a building regulations application, the installer must be registered with a competent person scheme such as FENSA or CERTASS (GOV.UK, 2026).
When a misaligned door signals a bigger problem
Signs of structural movement. If the door frame itself is out of square (the top and bottom gaps are uneven on both sides), the issue may be subsidence or a shifting wall. A spirit level placed across the frame will show if it is level. What to do. Contact a structural engineer or a chartered surveyor. Do not attempt to plane or shim a door if the frame is moving. Insurance. Most home insurance policies cover structural repairs caused by subsidence, but you must notify your insurer promptly (Royal Institution of Chartered Surveyors, 2026).
How to spot subsidence signs in your home
Frequently Asked Questions
The three most common causes are sagging from the door's weight, expansion or contraction of timber due to weather, and loose or worn hinges. According to the Energy Saving Trust, identifying the cause takes 30 seconds with a gap or level test.
Start by tightening hinge screws with a screwdriver; this costs nothing and solves many cases. If the door is sagging, add shims behind hinges or plane the door edge. For worn hinges, replace them for £10-£30, as per Checkatrade.
A DIY fix costs £0 if you tighten screws or plane the edge. Hiring a tradesperson ranges from £50 to £200 depending on the fix, with annual energy savings of up to £120, according to the Energy Saving Trust.
Yes, most sagging doors can be fixed yourself in under an hour. Tighten hinge screws, add shims behind the hinge, or plane the door edge. The Energy Saving Trust states this can save up to £120 a year on heating bills.
Call a tradesperson if the door still won't close after tightening screws and adding shims. If the frame is twisted or the wall is moving, contact a structural engineer. Typical trade costs range from £50 to £200, per Checkatrade.
