CDF’s ProBuilder tool allows contractors and facility managers to configure double door assemblies online. During pair configuration, ProBuilder validates that the coordinator, astragal, flush bolts, exit devices, and closers are compatible and correctly assigned to the active and inactive leaves. ProBuilder also checks fire rating compatibility across all components in the assembly and provides instant pricing.

For assistance with your double door configuration, call (855) 769-9895 or email sales@cdfdoors.com. CDF’s sales team is available Monday through Friday, 7:30 AM to 4:30 PM CT.

Configure Your Double Door Assembly

What is the difference between the active leaf and the inactive leaf on a double door?

The active leaf is the primary operating door used for daily traffic. It carries the lockset or primary exit device and swings freely without releasing any bolts. The inactive leaf remains closed most of the time and is secured by flush bolts or a surface vertical rod exit device at the top and bottom. The active leaf always closes second when a coordinator is present.

When do I need a door coordinator on a pair of doors?

A coordinator is required whenever a pair has an overlapping astragal. The coordinator ensures the inactive leaf closes first so the astragal overlaps correctly and the active leaf latch can engage. On fire-rated pairs, a coordinator is mandatory per NFPA 80. If the pair has no overlapping astragal and no fire rating, a coordinator may not be necessary.

Can I use two rim exit devices on a double door opening?

No. Two rim exit devices on a pair create a latching conflict at the meeting stile because both devices attempt to latch horizontally with no fixed strike point. The correct configuration is a rim exit device on the active leaf and a surface vertical rod (SVR) exit device on the inactive leaf. The SVR latches vertically into the frame head and floor.

What type of flush bolts are required on fire-rated double doors?

Fire-rated pairs require automatic (self-latching) flush bolts on the inactive leaf. Automatic flush bolts engage when the inactive leaf closes, ensuring positive latching without relying on manual action. Manual flush bolts are generally not permitted on fire-rated pairs because there is no guarantee they will be engaged during a fire event. The flush bolts must be UL listed for the specific fire rating of the assembly.

What is the difference between an astragal and a mullion?

An astragal is attached to one of the door leaves (typically the inactive leaf) and overlaps the gap between the two meeting stiles when both doors are closed. It moves with the door. A mullion is a fixed vertical member anchored to the frame head and floor, dividing the opening into two separate single-door openings. Astragals are standard on most commercial pairs and are required on nearly all fire-rated pairs. Mullions are used when a fixed center post is acceptable.

What are the fire rating levels available for double door assemblies?

Double door assemblies are available at five fire rating levels: 20-minute, 45-minute, 60-minute, 90-minute, and 3-hour (180-minute). The required rating is determined by the fire rating of the wall assembly the doors are installed in. All components of the pair (doors, frame, hinges, closers, exit devices, astragal, flush bolts, coordinator, and glazing) must be listed and labeled at or above the required rating. The entire assembly is rated to its lowest-rated component.

How do I determine the handing of a double door opening?

Stand on the outside of the opening (the key side, pull side, or corridor/public side). The hand is determined by the active leaf. If the active leaf hinges are on the right, it is a right-hand pair. If on the left, it is a left-hand pair. If the door swings toward you (push side becomes the outside), add "reverse" to the designation (RHR or LHR). The inactive leaf handing is always opposite the active leaf.

What happens if the astragal is missing on a fire-rated pair?

A fire-rated pair without an astragal will fail fire inspection. The gap between the meeting stiles allows smoke and flame passage, compromising the fire barrier. NFPA 80 requires that the gap between meeting stiles on fire-rated pairs be protected by a listed overlapping astragal. Adding an astragal after installation is possible but requires field modification that may not match factory preparation quality. Specify the astragal during the ordering process to avoid this issue.

Frequently Asked Questions

The following mistakes account for the majority of double door rework on commercial job sites. Each mistake, its consequence, and the correct approach are described below.

Wrong Coordinator Sequence

The coordinator arms are installed so they hold the inactive leaf open instead of the active leaf. Result: the active leaf closes first, trapping the astragal on the wrong side and preventing both doors from closing flush. On fire-rated openings, this constitutes a code violation because the fire barrier is compromised. The fix requires removing the coordinator, reversing the arm positions, and remounting.

Missing Astragal

The pair is ordered without an astragal, leaving an unprotected gap between the meeting stiles. On fire-rated openings, this is an automatic inspection failure. On non-rated openings, it results in light gaps, air infiltration, and reduced acoustic performance. Adding an astragal after installation requires field mortising or surface mounting, neither of which produces as clean a result as factory preparation.

Incorrect Active Leaf Designation

The lockset or primary exit device is installed on the leaf that should be the inactive leaf. Flush bolts are installed on the leaf that should be the active leaf. The coordinator holds the wrong leaf open. Every piece of hardware on both leaves is in the wrong position. This is the most expensive mistake to correct because it requires removing and reinstalling all hardware on both doors, and may require new door prep if the existing mortises are on the wrong stiles.

Fire-Rated Pairs Without Proper Hardware Coordination

A fire-rated pair is specified with a coordinator omitted, manual flush bolts instead of automatic, panic hardware instead of fire exit hardware, or an astragal that is not fire-listed. Any one of these errors results in a non-compliant assembly. The fire inspector will reject the opening, and the correction requires sourcing and installing the correct listed components. On large projects with dozens of fire-rated pairs, this error multiplied across many openings can delay occupancy and generate significant additional cost.

Two Rim Exit Devices on a Pair

Both leaves are specified with rim exit devices instead of a rim and SVR combination. Two rim devices create a latching conflict at the meeting stile because both attempt to latch horizontally against each other. Neither device has a fixed strike point. The inactive leaf rim device must be replaced with an SVR, which latches vertically into the frame head and floor.

Flush Bolts on the Active Leaf

Flush bolts are mistakenly mortised into the active leaf instead of the inactive leaf. This prevents the active leaf from swinging freely for daily use. The active leaf doors are now permanently prepped with flush bolt mortises that serve no purpose, and the inactive leaf has no bolt preparation. In many cases, both doors must be replaced.

Common Double Door Configuration Mistakes

The majority of double door rework results from specification errors that could have been caught during the ordering process. The following checklist covers every decision point that must be addressed when specifying a pair. Completing each item before ordering prevents the most common rework scenarios.

• Determine the active leaf: Identify which leaf will be used for daily traffic. This sets the handing and determines where the lockset or primary exit device is installed.

• Confirm the hand: Stand on the outside (key side or pull side) of the opening. Determine whether the active leaf hinges are on the left or right. Specify LH, RH, LHR, or RHR.

• Choose astragal or mullion: If the gap between leaves must be sealed (which is almost always the case), specify an astragal. If a fixed center post is acceptable, specify a mullion. For fire-rated openings, an overlapping astragal is almost always required.

• Determine if a coordinator is needed: If the pair has an overlapping astragal, a coordinator is required. If the pair is fire-rated, a coordinator is required. Specify the coordinator type compatible with the exit devices and closers on both leaves.

• Select flush bolts or surface bolts: For the inactive leaf, specify automatic flush bolts on fire-rated openings and manual or automatic flush bolts on non-rated openings. If the inactive leaf has an SVR exit device, flush bolts are not needed.

• Configure exit devices: If both leaves need exit devices, specify a rim device on the active leaf and an SVR on the inactive leaf. Do not specify two rim devices on a pair.

• Verify fire rating on every component: If the opening is fire-rated, confirm that doors, frame, hinges, closers, exit devices, astragal, flush bolts, coordinator, and glazing all carry listings at or above the required rating.

• Specify door closers on both leaves: Both leaves need closers. Closer sizing must account for door width and weight. On fire-rated pairs, closers must be UL listed for fire-rated service.

• Confirm leaf widths: Equal or unequal? If unequal, specify which leaf is wider and confirm that the frame is prepared for the correct leaf widths.

• Verify frame preparation: The frame must be prepared for the coordinator, closer brackets, exit device strikes, and flush bolt strikes at the head. Confirm all frame preps match the specified hardware.

How to Specify Double Doors Correctly to Avoid Rework

The critical rule for fire-rated pairs is that every component must be listed and labeled at or above the required rating. A 90-minute door paired with a 45-minute frame does not create a 45-minute assembly. It creates a non-compliant assembly. The entire opening is rated to the lowest-rated component.

Fire-rated pair assemblies must also meet NFPA 80 requirements for self-closing and positive latching. Both leaves must close and latch automatically without manual intervention. This means automatic flush bolts on the inactive leaf (or an SVR exit device), door closers on both leaves, and a coordinator to manage the closing sequence.

Fire-Rated Pair Component Checklist

The following table lists every component in a fire-rated pair and its fire rating requirement. Use this checklist to verify that all components are specified correctly before ordering.

Fire-rated double door openings are subject to more stringent configuration requirements than non-rated pairs. Every component in the assembly must be listed and labeled for the required fire rating, and the components must be tested together as a complete assembly. The following table lists fire rating levels and their pair-specific requirements.

Fire-Rated Double Door Requirements

The most common exit device error on pairs is specifying two rim devices instead of a rim and SVR combination. Two rim devices on a pair create a conflict at the meeting stile because both devices try to latch against each other with no fixed strike point. The SVR on the inactive leaf solves this by latching vertically into the frame head and floor rather than horizontally into the meeting stile.

When a double door opening is on an egress path, one or both leaves may require exit devices (panic hardware or fire exit hardware). The configuration depends on which leaves are in the egress path, whether the opening is fire-rated, and whether the inactive leaf needs to be operable for egress. The table below outlines common exit device configurations for pairs.

Exit Device Configuration for Pairs

A common mistake is specifying manual flush bolts on a fire-rated pair. Manual bolts rely on building occupants to engage them, which means the inactive leaf may not be secured during a fire event. Most AHJs require automatic flush bolts on fire-rated inactive leaves to ensure positive latching without human intervention.

The inactive leaf of a pair must be secured at the top and bottom when it is in the closed position. Two types of bolts serve this purpose: flush bolts and surface bolts. The choice between them affects aesthetics, fire rating compliance, and operational convenience. The following table compares the two bolt types.

Flush Bolts vs. Surface Bolts

The most damaging coordinator misconfiguration is reversed sequencing. If the coordinator arms are installed backwards or the coordinator is mounted incorrectly, it holds the inactive leaf open instead of the active leaf. This means the active leaf closes first, the astragal cannot overlap, the latch cannot engage the strike, and on fire-rated openings the assembly fails its closing sequence requirement. Correcting reversed coordinator arms usually requires removing the coordinator, repositioning the arms, and remounting.

A door coordinator is a device mounted on the frame head above a pair of doors that controls the closing sequence of the two leaves. Coordinators ensure the inactive leaf closes before the active leaf, which is necessary for the astragal to overlap correctly and for the active leaf latch to engage the strike. The table below describes coordinator types and application requirements.

Door Coordinators: What They Do and When They Are Required

The most common mistake is omitting the astragal entirely. Without an astragal on a fire-rated pair, the gap between the two leaves allows smoke and flame passage, and the assembly will fail inspection. On non-fire-rated pairs, a missing astragal results in visible light gaps, air infiltration, and reduced sound attenuation.

The gap between two meeting door leaves must be addressed for weather resistance, smoke and sound attenuation, fire rating, and security. Two components serve this purpose: astragals and mullions. They are not interchangeable, and selecting the wrong one creates problems that are difficult to correct after installation. The table below compares astragals and mullions across key criteria.

Astragal vs. Mullion: When to Use Each

Incorrect handing on a pair means all hardware is positioned for the wrong leaf. Hinges, locksets, closers, exit devices, coordinators, and flush bolts are all handed. Reversing the hand after hardware is installed requires a complete teardown and rehang of both doors.

Handing a pair of doors follows the same convention as handing a single door, but it is applied to the active leaf only. The inactive leaf handing is implied by the active leaf designation. The following table explains how to determine the hand of a double door opening.

Handing for Double Doors

The most common misconfiguration error is reversing which leaf is active and which is inactive. When the active leaf is designated incorrectly, the lockset or exit device ends up on the wrong door, flush bolts are installed on the wrong leaf, and the coordinator (if present) forces the wrong leaf to close first. This typically requires removing and reinstalling all hardware on both leaves.

Every double door opening consists of two leaves: the active leaf (also called the primary leaf or operating leaf) and the inactive leaf (also called the secondary leaf or fixed leaf). Understanding the distinction between these two leaves is the foundation of correct pair configuration. The table below summarizes the key differences between the active and inactive leaf.

Active Leaf vs. Inactive Leaf

This configuration guide is published by CDF Distributors and reflects industry-standard practices for specifying and configuring double door (pair) openings in commercial construction. The information is based on established hardware application principles documented by organizations including the Door and Hardware Institute (DHI), NFPA 80 (Standard for Fire Doors and Other Opening Protectives), and the International Building Code (IBC). CDF’s technical team reviews every pair configuration before fabrication to catch specification errors before they reach the job site.

About This Guide

Misconfigured double door openings are one of the most common sources of rework in commercial door installations. When a pair of doors is specified incorrectly, the consequences range from doors that will not close in the correct sequence to fire-rated assemblies that fail inspection. The most frequent errors involve incorrect active leaf designation, missing or wrong coordinators, incompatible astragal and mullion selections, and fire-rated pairs shipped without the hardware coordination required by code. This guide explains how each component of a double door opening works, what happens when it is configured incorrectly, and how to specify pairs correctly the first time.

CDF Distributors ships pre-configured double door assemblies from its Nashville, Tennessee headquarters. You can configure pair openings online using CDF’s ProBuilder tool at cdfdistributors.com, which validates hardware compatibility and coordinator requirements automatically. For assistance configuring a double door assembly, call (855) 769-9895 or email sales@cdfdoors.com.