Exterior Double Doors for Sale: Sizes & Specs Guide

What Are Exterior Double Doors?

Exterior double doors consist of two hinged door panels that meet in the middle and operate as a single unit. They are commonly specified for main residential entrances, patio access points, and commercial storefronts where a wider opening is required than a single door can provide. The two panels can be configured in several ways: both panels active (opening fully), or one active panel with the second panel fixed in place for daily use.

The primary advantage of double doors is the increased clear opening width they provide. This matters for moving large furniture, accommodating wheelchairs, creating a grand entry aesthetic, or meeting egress requirements in commercial buildings. When shopping for exterior double doors for sale, the two factors that will dominate your decision are the size of the opening you have to fill and the material you choose.

Standard Sizes and Dimensions

Before you begin comparing products, you need to know what dimensions are actually available. The door industry operates on a standardized sizing system, though custom sizes are always possible at a premium.

Standard widths and heights for exterior double doors (per door panel):

The total width of the double door unit is the sum of both panels. So a common configuration of two 3′ 0″ panels gives you a 6′ 0″ wide door system. The most frequently specified double door sizes are 5′ 0″, 5′ 6″, and 6′ 0″ total widths.

Panel thickness is fairly consistent at 1¾” for residential units. Commercial-grade doors may be thicker, typically 1¾” to 2¼”, depending on the fire rating and structural requirements.

Two important distinctions to keep in mind:

• Door unit size refers to the actual dimensions of the pre-hung door assembly, including the frame.
• Rough opening size refers to the framed opening in the wall that the door unit will be installed into. The rough opening is always larger than the door unit.

A standard rule of thumb is that the rough opening should be about 1″ to 1½” wider and ½” to ¾” taller than the door unit dimensions. This gap allows for shimming and leveling during installation.

How to Measure for Exterior Double Doors

Accurate measurement is the single most important step in the buying process. An incorrectly sized door will not function properly, will compromise the building envelope, and can void the warranty.

Measuring the rough opening:

• Measure the width at three points: the top, middle, and bottom of the framed opening. Record the narrowest measurement.
• Measure the height at both the left and right sides, from the subfloor or sill to the top of the framing. Record the shortest measurement.
• Check for square by measuring the diagonals. If the two diagonal measurements differ by more than ¼”, your opening is not square, and you will need to address this before installation.
• Check for level across the sill and plumb on both jambs.

Common measurement mistakes to avoid:

• Measuring only one point of the width and height. Framed openings are rarely perfectly true.
• Forgetting to account for flooring thickness. The finished floor height affects the final door height.
• Assuming the rough opening size equals the door size. It does not, as mentioned above.
• Not accounting for the astragal, the vertical strip that covers the gap between the two door panels. This adds to the overall width and must be included in the unit dimension.

If you are replacing an existing double door, measure the exterior dimensions of the current door unit, including the frame, rather than the interior panel dimensions. This gives you the closest match to the existing rough opening.

Material Options: Steel, Fiberglass, Wood, and More

The material you choose determines the door’s durability, maintenance requirements, thermal performance, and cost. Each option has a distinct profile that suits different project requirements.

Steel double doors are the most common choice for commercial applications and budget-conscious residential projects. They consist of a steel skin over an insulating foam core. Steel offers excellent security and dimensional stability, and it does not warp or swell like wood. The downsides are that steel dents relatively easily, and if the exterior finish is scratched, it can rust. For exterior use, look for doors with a galvanized or pre-finished surface.

Fiberglass double doors are the fastest-growing segment in the residential market. They are molded to mimic wood grain but are far more resistant to dents, rot, and insect damage. Fiberglass does not expand and contract with humidity changes the way wood does, making it a strong choice for climates with significant seasonal swings. These doors can be painted or stained, and they accept a wide range of finishes. They are generally more expensive than steel but less expensive than high-end wood.

Solid wood double doors remain the premium aesthetic choice. Mahogany, oak, and walnut are common species for exterior doors. Wood offers unmatched natural beauty and can be carved or shaped into custom designs. However, wood requires ongoing maintenance: periodic refinishing, careful attention to weatherstripping, and protection from direct sun and moisture. Solid wood doors are also the most expensive option and are best suited for covered entries that limit weather exposure.

Aluminum double doors are primarily a commercial product, though they are increasingly used in modern residential architecture. Aluminum offers slim sightlines, which means more glass and more natural light. It is extremely durable and corrosion-resistant, especially when thermally broken. The trade-off is lower thermal performance compared to fiberglass or insulated steel unless you specify a thermally broken system with high-performance glazing.

Glazing and Energy Efficiency

The glass area of a double door is often the deciding factor for both aesthetics and energy performance. A door with a large glass panel will let in more light but will generally have a lower overall insulation value than a solid door.

Double glazing refers to two panes of glass with an air or gas-filled space between them. This is the minimum standard for exterior doors in most climate zones. The space is typically filled with argon or krypton gas to reduce heat transfer, and the glass is coated with a low-emissivity (low-E) coating that reflects heat while allowing visible light through.

When evaluating glazing, look for two performance ratings:

• U-factor measures how well the door prevents heat from escaping. Lower is better. A U-factor of 0.30 or below is considered good for a door with glazing.
• Solar Heat Gain Coefficient (SHGC) measures how much solar radiation is transmitted through the glass. Lower SHGC means less heat gain in summer. The ideal SHGC depends on your climate.

For a double glazed double door, the glazing is the weakest thermal link in the assembly. If energy efficiency is a priority, select a door with a smaller glass area, or specify triple glazing for extreme climates. Also check the edge spacer material — warm-edge spacers reduce heat loss at the glass edge compared to standard aluminum spacers.

Cost Considerations: Finding the Right Balance

The price range for exterior double doors is substantial, and the cheapest option is rarely the best value. Understanding where costs come from helps you make an informed trade-off.

Cost drivers:

• Material (steel is the entry point, wood is the premium)
• Glazing (larger glass areas and higher-performance glass increase cost)
• Pre-hung vs. slab (pre-hung units with frames cost more but install faster and more accurately)
• Hardware (hinges, handles, locksets, and astragals vary widely in quality and price)
• Custom sizing and design (non-standard dimensions and decorative detailing add cost)

Finding affordable options without sacrificing quality:

• Choose a standard size. Custom sizes can add 20-30% to the door cost. If your rough opening is close to a standard size, adjust the framing to fit a standard unit.
• Select steel or fiberglass over wood. These materials offer the best durability per dollar.
• Limit decorative glass. A full-lite door with a large glass panel costs more than a door with a smaller, divided-lite glass configuration.
• Buy a pre-hung unit. While the upfront cost is higher than a slab door, the installation labor is significantly reduced, and the result is more reliable.
• Compare the total installed cost, not just the door price. A cheap door that requires extensive site modification or frequent maintenance is not a bargain.

Common Questions About Exterior Double Doors

How secure are double doors?
Double doors present a unique security challenge because the meeting point of the two panels creates a potential weak spot. The astragal must be reinforced, and the doors should have multipoint locking systems that engage at multiple points along the frame. Look for hardware that meets ANSI/BHMA Grade 1 or Grade 2 standards, which indicates tested strength and durability.

Are double doors energy efficient?
Yes, if specified correctly. The efficiency depends on the material, the glazing, and the quality of the weatherstripping around both panels and the astragal. A well-sealed fiberglass double door with double glazing can perform comparably to a single high-quality door. The key is to ensure the astragal has continuous weatherstripping and that the door is properly installed with no gaps in the seal.

Do double doors add value to a home?
They can, particularly when they enhance the architectural character of the home and provide functional benefits like wider access. However, the value added depends on the overall style of the home and the local real estate market. A double door that looks out of place on a modest house may not return its cost.

Related Considerations: Matching Doors to Your Project

The right double door for your project depends on the specific conditions of your site and your performance priorities.

High wind zones: If the property is in a coastal area or a region prone to severe storms, the door must meet the local wind load requirements. This typically means a reinforced frame, impact-rated glazing, and stronger hinges and hardware. Steel and fiberglass doors are generally better suited to these conditions than wood. Always verify that the door you select has the appropriate design pressure rating for your location.

Historic or traditional homes: For period properties, a mahogany double door with divided lites is often the most appropriate choice. The wood can be matched to existing trim and millwork, and the door can be finished to complement the home’s character. Be prepared for the maintenance commitment that wood requires.

Modern architecture: For contemporary designs, a glass panel double door with aluminum framing delivers the clean lines and abundant natural light that define the style. Specify a thermally broken frame and low-E glazing to maintain comfort and energy performance.

Commercial applications: Steel double doors are the standard for commercial storefronts and office entrances due to their durability, security, and code compliance. They are available with fire ratings where required, and they withstand the heavy daily use of a public entrance.

Budget-conscious projects: Steel doors offer the lowest upfront cost and the best durability per dollar. Choose a pre-hung unit in a standard size, and invest the savings in quality hardware and proper installation.

How we meet these standards: As a manufacturer of exterior doors and windows, our approach at Jusen Door and Windows is to build these specifications into every unit we ship. We produce steel, aluminum, and wood double doors to order, with full customization on size, glass configuration, and hardware. Our factory direct supply model removes the middleman markup, and our pre-shipment inspection includes air-tightness, water-tightness, and wind resistance testing to verify performance before the doors leave our facility. We also adjust the profile structure and fittings to match local building codes for your target market, and we handle FCL and LCL shipping with full customs documentation. If you need a specific size that falls outside the standard range, our OEM and ODM capabilities allow us to manufacture to your exact specifications.

One final consideration: verify your local building codes before purchasing. Requirements for egress, fire ratings, and energy performance vary by jurisdiction. A door that is compliant in one state may not be in another. Confirm the requirements with your local building department or a qualified installer before you place your order.

Once you have your rough opening measurements and have selected your material and glazing, you are ready to compare products with confidence. The right exterior double door will provide years of reliable service, and the time spent on measurement and specification is the best investment you can make in the project.

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