A French door size can describe a single door slab, a pair of doors, or a complete unit with its frame. Those measurements are related, but they are not interchangeable. This guide covers common single and double French door sizes, interior and exterior configurations, how to measure an existing opening, and why the final rough opening must be checked against the selected product’s installation drawing.
What Is the Standard Size of a French Door?
There is no single standard size for every French door. The dimensions below are common planning references, while actual availability depends on the product line, frame, material, and whether the door is designed for interior or exterior use.
Common reference heights include 80 inches, with taller options such as 84 and 96 inches available in some product lines. Single-door widths are often discussed in the 18-to-36-inch range, while paired doors are commonly compared by their overall nominal width.
Before using any size chart, check whether a listed dimension refers to one door slab, both slabs together, or the complete framed unit. Door thickness and the required installation opening must be confirmed for the specific product.
Standard Single French Door Sizes
A single French door can work where one glazed leaf suits the opening and the available swing space. The size examples below are for comparing nominal door dimensions; they are not a list of sizes stocked by every manufacturer. Check the selected product’s available width and height combinations, frame dimensions, and required opening before ordering.
| Nominal height | Width references | Illustrative size examples |
|---|---|---|
| 80 in. | 18, 24, 28, 30, 32, or 36 in. | 30 × 80 or 36 × 80 in. |
| 84 in. | Check the selected product line. | 30 × 84 or 36 × 84 in., where offered |
| 92½ in. | Product-line dependent | No universal width combination |
| 96 in. | Product-line dependent | Verify available widths |
These are nominal planning references, not a stock list or rough-opening schedule. Confirm the selected door slab, complete-unit dimensions, and required installation opening before ordering.
A 30- or 36-inch single door can be a useful starting point, but its nominal slab width does not tell you the clear passage width or the size of the complete unit. Check the frame, swing clearance, and intended use before choosing between the sizes shown in the chart.
Standard Double French Door Sizes
Double French doors use two leaves, but a listed width may describe the pair of slabs or a complete framed unit. The examples below help compare nominal paired-door sizes; they do not establish which combinations are available for an interior or exterior product. For a patio door, confirm the complete unit, sill, swing direction, and installation opening separately.
| Nominal height | Paired-width references | Illustrative size examples |
|---|---|---|
| 80 in. | 36, 48, 56, 60, 64, or 72 in.; availability varies | 60 × 80 or 72 × 80 in. |
| 84 in. | Check the selected product line. | 60 × 84 or 72 × 84 in., where offered |
| 92½ in. | Product-line dependent | No universal width combination |
| 96 in. | Product-line dependent | Verify available widths |
Widths shown here are nominal references for a paired configuration. They do not establish the individual leaf width, outside frame width, clear passage width, or required rough opening. Confirm those measurements for the selected unit.
Exterior French Door Sizes
For exterior French doors leading to a patio, garden, or balcony, compare the overall configuration as well as its nominal width and height. Paired-door planning examples include 48 × 80, 60 × 80, and 72 × 80 inches (width × height). A taller option, such as 72 × 96 inches, may be available in a particular product line.
These are planning examples, not guaranteed stock sizes or rough-opening dimensions. Before changing an exterior opening, confirm the selected unit’s frame dimensions, sill, swing direction, and installation requirements.
Interior French Door Sizes
Interior French doors can separate a home office, living area, or bedroom while allowing light to pass between rooms. When comparing examples, use a consistent width × height order: a single door might be listed as 30 × 80 or 36 × 80 inches, while a paired configuration might be listed by an overall nominal size such as 48 × 80 or 60 × 80 inches. Taller options depend on the chosen product line.
Interior doors do not require the same exterior weather detailing, but the slab size still differs from the size of a framed unit and its required opening. For other interior door types, see our standard interior door sizes guide.
Rough Opening Sizes for French Doors
A door slab, a complete prehung unit, and a rough opening are different measurements. The opening must accommodate the selected unit and the installation clearances required for that product.
The chart below shows arithmetic examples using an assumed allowance of 2 inches in width and 2½ inches in height beyond the listed slab dimensions. These figures illustrate how a slab size and a larger opening can be related; they are not the specified rough openings for every French door. A paired door, exterior sill, frame design, or different installation system can require other dimensions. Before ordering or framing, confirm the required rough-opening width and height against the installation drawing for the complete door unit you select.
For a closer look at one nominal width, see our 36-inch door rough-opening guide. The examples below help explain why a door slab and the opening around an installed unit are different sizes.
| Example slab width | 80 in. slab height | 84 in. slab height | 92½ in. slab height | 96 in. slab height |
|---|---|---|---|---|
| 18 in. | 18 × 80 → 20 × 82½ in. | 18 × 84 → 20 × 86½ in. | 18 × 92½ → 20 × 95 in. | 18 × 96 → 20 × 98½ in. |
| 24 in. | 24 × 80 → 26 × 82½ in. | 24 × 84 → 26 × 86½ in. | 24 × 92½ → 26 × 95 in. | 24 × 96 → 26 × 98½ in. |
| 28 in. | 28 × 80 → 30 × 82½ in. | 28 × 84 → 30 × 86½ in. | 28 × 92½ → 30 × 95 in. | 28 × 96 → 30 × 98½ in. |
| 30 in. | 30 × 80 → 32 × 82½ in. | 30 × 84 → 32 × 86½ in. | 30 × 92½ → 32 × 95 in. | 30 × 96 → 32 × 98½ in. |
| 32 in. | 32 × 80 → 34 × 82½ in. | 32 × 84 → 34 × 86½ in. | 32 × 92½ → 34 × 95 in. | 32 × 96 → 34 × 98½ in. |
| 36 in. | 36 × 80 → 38 × 82½ in. | 36 × 84 → 38 × 86½ in. | 36 × 92½ → 38 × 95 in. | 36 × 96 → 38 × 98½ in. |
Illustrative calculation only: each arrow assumes an added 2 in. of width and 2½ in. of height. This table does not specify an available French door product or its actual required rough opening. Use the selected manufacturer's complete-unit drawing for final dimensions.
Two nominally 30-inch-wide door slabs add up to 60 inches of slab width. That figure alone does not establish the outside width of a paired prehung unit or its required rough opening. The frame, meeting detail, threshold, and product-specific installation clearance must also be considered.
Record the existing opening and compare it with the selected complete unit’s dimension drawing before ordering or changing the framing. For a broader explanation of door sizes and framed openings, see our door rough-opening sizes guide.
How to Measure for French Doors?
Before choosing a French door size, identify what you can actually measure: an exposed rough opening, an existing door frame, or the finished space between trims. Record the width and height at several points, note the floor or threshold used as the height reference, and keep a photo of the opening. These site measurements help you compare products, but the selected door unit’s dimension and installation drawings determine the size to order.
Step 1: Gather Your Tools
You will need a tape measure, a pencil, and a way to record the dimensions. A quick sketch of the opening is useful: mark the surfaces you measured between and note any existing frame, threshold, or finished flooring. Keep the readings for the top, middle, and bottom widths and for the height at each side and the center.
Step 2: Clear the Area
Shift any furniture or décor out of the way to create room to work. Make sure the frame is easy to reach and check that it isn’t bent or damaged — that could throw off your measurements.
Step 3: Measure the Width
First identify what you can measure: an exposed framed opening, an existing door frame, or only the finished space between trims. These are different reference points. Measure the available width near the top, middle, and bottom, record all three readings, and note the surfaces you measured between. The smallest reading identifies the tightest point; it is not automatically the door size to order.
Step 4: Measure the Height
Measure the height at the left, center, and right using the same top and bottom reference surfaces each time. Record all three readings and note whether the bottom reference is the subfloor, finished floor, or existing threshold. Different readings may reveal an uneven opening; compare the recorded site condition with the selected door’s installation requirements before confirming a size.
Step 5: Measure the Depth
Measure the wall depth where the new frame will sit and record any difference between the interior and exterior finishes. Also note the existing threshold, trim, and the direction in which the doors need to swing. These details help you compare the opening with the selected frame and installation drawing.
If you are sourcing wooden doors for several rooms or a larger project, our guide to wooden door manufacturers in China can help you research potential suppliers. Confirm the dimensions and specifications of the particular door you select before placing an order.
Custom vs. Standard French Door Sizes
Now that you know the standard measurements, let’s talk about when they work — and when they don’t.
Standard French Door Sizes
A commonly listed size is a practical starting point, but the same nominal size can refer to different slab or complete-unit measurements across product lines. Before selecting a door, compare its frame dimensions, swing direction, glazing, and availability with your recorded opening. Explore George Group’s door and window options, then confirm the dimensions and lead time of the specific unit you are considering.
Custom French Door Sizes
A custom configuration may be worth exploring when the existing opening, preferred swing, glazing, frame material, or design cannot be matched to a suitable listed unit. An older doorway or a larger opening does not automatically require a custom door: check the available configurations of the product you intend to use first.
For a custom order, confirm the approved drawings, complete-unit dimensions, required installation opening, price, and lead time before changing the site opening or placing the order.
Common Mistakes When Choosing French Door Sizes
While choosing the French door size, there are a few mistakes people commonly make that can cause problems later. We have listed a few common ones below so you can see them. These include:
- Ignoring the Rough Opening: The slab size alone won’t cut it. The frame and shims require additional space, so measure beyond the door itself.
- Neglecting Swing Room: Check the full swing of each door leaf against nearby walls, furniture, handles, and walkways. If the available space is limited, compare the selected French door with a sliding configuration before committing to the opening.
- Overlooking Clear Passage Width: A nominal 30-inch door does not guarantee 30 inches of usable passage. Check the clear opening with the door in its intended open position, especially if furniture or large items must pass through it.
- Overlooking Door Proportions: A taller door may suit a room with a high ceiling, but height alone should not determine the choice. Compare the selected product’s available sizes with the opening, frame, glazing, and surrounding wall proportions.
- Blocking Furniture Flow: Even beautiful double doors won’t work if they collide with sofas, dining sets, or cabinets. Always map out your room layout in advance.
Final Thoughts
Start with the space the French door needs to serve. Compare single and paired configurations, allow for the door swing, and distinguish the listed door size from the complete unit and the opening in the wall.
For a home renovation, record the available width, height, floor level, and photographs of the existing opening. For a project with multiple doors, compare site measurements with the door schedule and selected product drawings before the openings are finalized. In either case, confirm the manufacturer’s required rough opening before ordering or framing.
More French Door Ideas
Have an opening to check? Share its width and height measurements, a photo of the doorway, and whether you need an interior or exterior French door. If you are coordinating several openings, include the door schedule or relevant drawing. George Group can use these details to discuss suitable options and identify the product dimensions that need confirmation before ordering.
