French Door Repair

French doors rely on two opening leaves meeting accurately at the centre. A small change in one leaf can affect the other, leaving a rubbing edge, a gap or a lock that refuses to engage. Looking at the pair together is more useful than treating the handle side as an isolated fault.

From a Weston-super-Mare base, Sean Cardwell Windows covers Bristol and North Somerset. When describing a problem, say which leaf you normally open first and whether either one catches the floor or threshold. Mention any recent change in operation, rather than repeatedly forcing the handles.

The slave leaf and its shoot bolts

The less frequently opened leaf is often called the slave or inactive door. Depending on the design, shoot bolts secure it into the head and threshold before the everyday leaf closes against it. Some systems use a handle-operated mechanism instead of separate exposed bolts.

Debris in a bottom socket can stop a bolt travelling fully. Misalignment, worn bolt guides or a damaged mechanism can cause similar resistance. A leaf that looks shut may still be unsecured if its bolts have not engaged, so the repair check needs to include their travel and seating.

Alignment at the centre and threshold

Hinge wear or poor glazing support can allow either sash to drop. On paired doors, the centre meeting line provides a useful clue, but the outer frame gaps and threshold clearance must also be checked. Correcting one leaf without considering its partner can transfer the problem across the opening.

Appropriate hinge adjustment or repacking of glazed units may restore the geometry where components remain sound. Significant movement in the frame or building requires further investigation. Grinding away a catching edge or repositioning keeps immediately can compromise the intended fit instead of resolving its cause.

Multipoint locks and weather seals

The active leaf commonly carries a multipoint lock, although arrangements differ between manufacturers. The handle, cylinder, gearbox and locking points each need checking. A mechanism that works freely when open but binds when shut may be encountering resistance from the other leaf or its keeps.

At the meeting stile, overlapping profiles and gaskets help resist draughts and rain. Flattened seals, incorrect compression or damage to the central cover strip can affect that protection. Any replacement gasket must suit the system; adding bulky adhesive foam can interfere with both closing order and lock engagement.

When repair stops being the sensible option

Serviceable frames and sound leaves usually justify investigating compatible replacement hardware before discussing a whole new set. The decision changes where profiles are cracked, fixing points are badly damaged or obsolete parts cannot be matched safely. Replacement may also suit a planned change to the opening or threshold.

A completed repair should be checked with each leaf operating separately and then with the pair secured in their proper sequence. Drainage paths should remain open, and locking should not require lifting a leaf by its handle. If comparing new French doors with a sliding alternative, consider usable access, furniture and the space needed for swinging leaves.