French Doors or a Sliding Patio Door? A Decision Guide

If you are replacing a patio door, you can usually have either type in the opening you already have. This guide is part of our California window guide and compares the two on the points that affect daily use. For the replacement process itself, see our sibling guide to sliding patio door replacement.

The short version

Swing space

This decides more cases than anything else. A hinged door sweeps an arc as wide as the leaf. A pair of three-foot leaves swinging in takes roughly three feet of floor depth across a six-foot width that cannot hold a chair, a rug edge or a plant.

• In-swing uses interior floor. It suits rooms with space to spare and patios that are small, furnished up to the wall, or covered in snow in winter.
• Out-swing uses the patio or deck. It suits small rooms, but the leaves need somewhere to go, and an open leaf catches wind.
• Sliding uses neither. In a dining nook, a bedroom, or a kitchen with a table by the door, that settles it.

The Residential Code has a say outdoors. It requires a landing or floor on each side of each exterior door, at least as wide as the door and at least 36 inches in the direction of travel. A door may not simply open over a step-down into the yard unless it fits a narrow exception, and that exception requires that the door not swing over the stairs. If your patio is a step or two below the floor, an out-swing door needs a proper landing built for it.

How much opening you actually get

A two-panel slider opens half its width at most. A six-foot slider gives you a walk-through a little under three feet wide. A six-foot pair of French doors with both leaves open gives nearly the full six feet.

That matters for moving furniture, for parties, and for the feeling of a room that opens to the yard. It matters less than people expect day to day, because most households open one leaf of a French door and leave the other bolted. If the wide opening is the goal, compare French doors with the larger systems in our guide to multi-slide and folding glass doors.

View and light

Sliders have narrower frames around larger panes, so the same opening gives more glass. French doors have a wider frame around each leaf plus the meeting stiles in the middle. Add divided lites and the view is broken up further, which is the point stylistically and a loss if you bought the house for the view.

If you want the look of French doors with less frame, ask whether the brand you are considering offers a sliding door built with wider rails to resemble hinged doors.

Sealing against air and water

Hinged doors

A hinged door closes against compression weatherstripping on three sides, like a refrigerator door, and that kind of seal is tight and long-lived. The weak point is the bottom. The threshold has to stop water while staying low enough to step over, and the meeting stiles of a double door have to seal against each other. Out-swing doors have an advantage in storms because wind pushes the leaf harder against its seals. In-swing doors rely on the sill detail and sweep, and they are the type more likely to show water at the threshold on an unprotected west or south wall.

Sliding doors

A slider cannot compress a gasket, since the panel has to move past it. It uses brush or fin seals and an interlock where the panels meet, and it manages water by draining the sill through weep holes. That system works well when the track is clean and the patio is lower than the sill, and it leaks when the weeps are blocked. It also wears: seals flatten and rollers settle, so a slider needs occasional adjustment to stay tight.

On a covered patio either door is fine. On a wall with no overhang that faces the weather, an out-swing hinged door or a slider with a taller sill is the safer choice, and the installation matters more than the type. See our sibling guide to flashing and waterproofing.

Energy code: the same for both

California's Energy Code does not distinguish between them. A door with glazing of 25 percent or more of its area is a glazed door, and glazed doors must meet fenestration requirements. The Energy Commission's compliance manual says most sliding glass doors and French doors meet that definition.

A replacement of either type therefore has to meet the maximum U-factor and SHGC for your climate zone, shown on the NFRC label for the whole door: U-factor 0.27 in Sacramento, the Bay Area and Tahoe, and SHGC 0.23 where an SHGC limit applies. A single door replaced on its own usually falls under the 75-square-foot exception with its looser figures. Because French doors have more frame and less glass, their whole-door numbers can differ from a slider with identical glass, so compare labels rather than glass packages. Details are on what Title 24 requires.

Safety glazing: the same for both

Under Section R324.4.1 of the 2025 California Residential Code (formerly R308.4.1), glazing in fixed and operable panels of swinging, sliding and bifold doors is a hazardous location and must be safety glazing. Sidelights and windows within 24 inches of the door are covered by the next subsection. Factory-built doors come with compliant, marked glass. Our page on tempered glass requirements has the full list of locations.

Security

Each type has a known weak point and a known answer.

• French doors. The inactive leaf is held only by bolts into the head and the sill, and the active leaf locks to that leaf rather than to a solid jamb. Look for multi-point locking that throws bolts at the top and bottom as well as the center. Milgard states that its V400 Tuscany in-swing and out-swing patio doors feature multi-point locking hardware made of stainless steel. Out-swing doors expose their hinges, so they should have hinges with non-removable pins or security studs.
• Sliding doors. The historic problems were a single latch and panels that could be lifted off the track. Look for a multi-point lock, anti-lift blocks at the head, and a secondary foot bolt.

For both, the glass is the largest target. Tempered glass meets the safety rule but breaks out completely. Laminated glass stays in the opening when cracked. If security is a priority, ask for laminated glass in either door. More in our sibling guide on window and door security.

Screens

Californians live with their patio doors open for half the year, so the screen deserves more thought than it gets.

• Sliding doors take a sliding screen on its own track outside the glass. It is simple, cheap to replace and easy to use, and it is also the part of the door most often damaged.
• In-swing French doors can take a sliding or retractable screen on the exterior.
• Out-swing French doors need the screen on the inside, which usually means a retractable screen that rolls into a housing at the jamb. These work well and cost more.

If you have pets or small children, ask about heavier screen mesh at order time. Our page on screen replacement covers mesh types.

Accessibility and everyday use

A sliding door asks very little of the user: one hand, no stepping back, and it stays open at any position. That makes it the easier door for anyone carrying a tray, using a walker, or managing a wheelchair. The obstacle is the sill track, which on a standard slider stands above the floor. Low-profile sills are available on some lines, at some cost in water resistance.

A hinged door needs the user to pull the leaf toward them and step around it, or push it out and reach to close it. It can, however, be fitted with a lower threshold and gives a wider clear opening when both leaves are open.

The Residential Code is relevant in one specific case. Every dwelling needs one egress door that is side-hinged, with a clear width of at least 32 inches and a clear height of at least 78 inches. A sliding door can never be that door. In most houses the front door fills the role and the patio door is free to be anything. In an accessory dwelling unit, a garage conversion, or a studio where the patio door is the only door, it has to be hinged. Our sibling guide on ADU windows and doors covers this.

Style

French doors belong to traditional architecture: craftsman bungalows, Spanish and Mediterranean revival, Tudor, colonial and farmhouse styles. Sliding doors belong to post-war and contemporary architecture: ranch houses, Eichlers and other mid-century modern homes, and current modern builds.

You can cross those lines, but it shows. A vinyl slider in a 1920s bungalow dining room looks like a later alteration, and divided-lite French doors in an Eichler work against the house. If your home has a strong style, let it lead. Our guide to choosing a window style applies the same thinking to windows.

Maintenance

• Sliding: vacuum the track, keep the weeps clear, adjust or replace rollers when the panel starts to drag, and replace worn seals.
• French: keep hinges tight, adjust the strike and bolts as the house moves, replace the door sweep when it wears, and on wood doors keep every edge sealed, including the top and bottom.

Neither is demanding. A hinged door has more hardware to keep aligned; a slider has a track that collects whatever the patio sends it.

Which one we would choose

• Small room, furniture near the door, or a house with modern lines: sliding.
• Traditional house, covered patio, and room for the swing: French.
• Exposed wall with no overhang: out-swing French, or a slider with a full-height sill, with careful flashing either way.
• Someone in the house with limited mobility: sliding, with attention to sill height.
• The only door into the space: hinged, because the code requires it.
• A view you paid for: sliding, or a larger glass wall system.

Cost depends more on material, size and glass than on type. See our cost page for current ranges and how to compare quotes.

Sources

• 2025 California Residential Code, Chapter 3: Sections R318.2 (egress door), R318.3 (landings at exterior doors) and R324.4 (hazardous locations for glazing)
• 2025 Building Energy Efficiency Standards: definition of glazed door, Section 150.2(b)1B, Table 150.1-A
• 2025 Single-Family Residential Compliance Manual, Chapter 3
• Milgard swinging patio doors and Milgard sliding glass doors

Working with Heritage Exteriors

We install both types and have no reason to steer you toward either. We will measure the swing against your furniture and patio, check the landing and sill height, and tell you if the door you want will be a problem on that wall. Licensed in California, CSLB #1055919. Call (916) 546-2991.