Sliding patio doors or French doors: which is right for your room?

Opening area

French doors open the full width of the frame once both leaves swing back, which is hard to beat if you want the widest possible gap between inside and outside for entertaining or moving furniture through.

Sliding patio doors typically only open to half the total frame width, since one panel slides behind the other, so a 3 metre patio door set gives roughly 1.5 metres of clear opening rather than the full 3 metres.

Floor space, inside and out

This is usually the deciding factor. French doors need clear space for the leaves to swing, both inside the room and outside on the patio, so a table pushed close to the doors or a step straight outside can rule them out.

Sliding doors don't swing at all, they run on a track, so furniture can sit closer and there's no swept arc to plan around, which is why they're often preferred in smaller kitchen extensions.

Track maintenance vs hinge maintenance

Sliding doors run on a track that needs occasional cleaning, since grit and debris in the channel is the main cause of a patio door becoming stiff to slide, and the rollers can wear over years of heavy use.

French doors run on hinges rather than a track, so there's no channel to keep clear, but the hinges themselves and the shootbolt keeps benefit from an occasional check and a drop of lubricant to keep everything moving smoothly.

Security

Both can be specified to a high security standard. French doors use a multi-point lock on the master leaf and shootbolts on the slave leaf; sliding doors use a hook or roller multi-point lock along the sliding edge that engages into the frame at several points, plus an anti-lift feature in the track to stop the moving panel being jemmied upward and out.

Neither is inherently weaker when specified properly with a TS007 3 star cylinder and PAS 24 tested hardware; the difference comes down to installation quality more than door type.

Glass weight and panel size

Sliding doors typically carry larger single panes of glass than a French door leaf, since there's no central meeting hinge splitting the opening into two narrower leaves. That larger glazed unit is heavier, which is why sliding door rollers and tracks are built to a higher load rating than door hinges.

• French doors: full width opening, needs swing clearance, hinge based
• Sliding patio doors: half width opening, saves floor space, track based
• Both: can be specified with TS007 3 star cylinders and PAS 24 hardware

Thermal performance and Window Energy Ratings

Both door types can be specified with a similar glazing package, a double glazed unit with low-E coating, argon fill and a warm edge spacer, so the frame style itself doesn't dictate thermal performance in the way people sometimes assume. What does differ is the sheer glass area: a sliding door's larger single panes mean glazing performance has a bigger influence on the whole unit's Window Energy Rating than the same glazing spec would on a French door leaf split into two narrower panes.

Trickle vents may be specified on either door type where Part F ventilation requirements apply to the room, though this is decided at survey rather than being automatic on every job.

Who tends to choose which

Homeowners extending a kitchen diner with limited patio depth usually lean toward sliding doors, simply because there's nowhere for a swinging leaf to go without hitting outdoor furniture or a boundary. Anyone replacing tired 1990s patio doors on a period property, or wanting the traditional look of hinged doors opening onto a garden, tends to prefer French doors instead, particularly where the room already has generous floor space either side of the opening.

Cost and which suits which room

Our French doors start from £1,499 fully fitted. As a broad UK guide, sliding patio doors of a comparable size often sit in a similar bracket to slightly higher, largely driven by the larger glazed units and track hardware rather than the frame itself; this is a general market range, not a CW Doors quote.

As a rule of thumb, choose sliding doors where floor space is tight on either side, and French doors where you want the widest possible opening and have the clearance to use it.