Manual Flush Bolts

Manual flush bolts are the hardware installed on the inactive leaf of a pair of double doors to anchor it to the head frame and the floor when the inactive door is not in use. On a double door opening that has no center mullion, one door serves as the active leaf that opens and closes normally, and the other serves as the inactive leaf that stays fixed most of the time. The manual flush bolt is what keeps that inactive leaf from moving. Without it, both doors would swing freely and the latch on the active leaf would have nothing solid to engage.

This category covers manual flush bolts across all compatible door types: hollow metal, composite wood, and aluminum door applications, from brands including Ives, PDQ, Don-Jo, Hager, Imperial, Trimco, and Rockwood.

What Is a Manual Flush Bolt?

A manual flush bolt, also called a door flush bolt or flush lock, is a surface or mortise-mounted bolt that slides into a strike at the top of the door frame header and into a floor strike at the threshold. It's operated by hand using a lever, knob, or spring-loaded actuator on the edge of the door. The bolt projects and retracts manually, meaning someone has to physically operate it when the inactive door needs to be opened or secured.

This is the defining difference from an automatic flush bolt, which retracts automatically when the active door opens, and a constant latching flush bolt, which keeps the inactive door latched at all times until the active door is opened and triggers the release. Manual flush bolts are the simplest and most common type in commercial construction and the most widely specified on standard double door openings that don't require automatic sequencing.

Standard Specifications: What to Know Before Ordering

Most manual flush bolts across all brands and door types share a common dimensional standard. The standard rod length is 12 inches, measured from the center of the flush bolt body face to the bolt end in the retracted position. This 12-inch rod length is designed to match the standard ANSI door preparation so the top and bottom bolts reach their respective strikes in a standard height door. On doors over 7'-6" tall, an 18-inch rod length is typically required and must be specified separately.

Bolt throw is typically 3/4 inch on commercial grade manual flush bolts, with a 3/4-inch backset and 7/8-inch vertical adjustment to accommodate minor alignment variations during installation. The bolt diameter is 1/2 inch on most commercial models. All products in this category are non-handed and install on either the top or bottom edge of the inactive door.

Manual Flush Bolts for Metal Doors

Ives FB457 Manual Flush Bolt

The Ives FB457 is the most widely specified manual flush bolt for hollow metal door applications. Body dimensions are 1-1/4" W x 6-3/4" L x 1-1/8" D with a 12" rod length, 3/4" throw, and 1/2" diameter bolt tip. The round bolt head design requires only a punched hole in the metal frame, with no routed pocket required. An anti-rotation feature on the flat-sided bolt tip prevents the bolt from spinning during operation. Certified ANSI/BHMA A156.16, L04251. UL listed for 90-minute fire doors up to 8'-0" x 10'-0".

Ives FB458 Manual Flush Bolt

The Ives FB458 is the single flush bolt version for metal doors, also meeting ANSI/BHMA A156.16 L04251 and UL listed for 90-minute fire doors. Smaller profile than the FB457, used when only a top or bottom bolt is required rather than a set.

PDQ 93170 Series Manual Flush Bolt

The PDQ 93170 is the manual flush bolt for hollow metal double doors, certified ANSI/BHMA A156.16 Type L04251. Features a 3/4" slide bolt throw, 3/4" backset, and standard 12" rod length. UL/CUL listed for use with certified swinging-type fire doors rated up to 1-1/2 hours. Fastened with 16 #8 x 3/4" flat head combination screws. The PDQ 909 dust proof strike is recommended for the bottom application to prevent dirt accumulation and clogging in the floor strike.

Don-Jo 1550 and 1555 Flush Bolts

The Don-Jo 1550 is a 15/16" x 4-1/4" aluminum door flush bolt. The 1555 is the metal door version. Both are value-positioned manual flush bolts for applications where institutional-grade Ives or PDQ hardware is not required.

Trimco 3915 Manual Flush Bolt

The Trimco 3915 is a manual flush bolt for metal doors, specified on projects that call for Trimco hardware to maintain hardware schedule consistency across the opening.

Manual Flush Bolts for Wood Doors

Ives FB358 Manual Flush Bolt

The Ives FB358 is the standard manual flush bolt for wood double doors. Body dimensions are 1" W x 6-3/4" L x 1-3/8" D with a mortise-style installation that routes into the door edge for a clean, recessed finish. Certified ANSI/BHMA A156.16, L04261. UL listed for 90-minute fire doors up to 8'-0" x 10'-0". When the active door is opened, the lever moves to the up position retracting the bolt. When the inactive leaf closes, the lever moves down projecting the bolt into the strike.

PDQ 93270 Series Manual Flush Bolt

The PDQ 93270 is the wood door counterpart to the PDQ 93170, engineered for composite wood door applications.

Dust Proof Strikes for Door Flush Bolts

The floor strike on a manual flush bolt installation is the component most vulnerable to debris accumulation, especially on doors that are kept in the flush bolt-secured position for extended periods. Dirt and grit collect in the floor strike and prevent the bolt from engaging fully. Ives DP1 and DP2 dust proof strikes are recommended on the bottom application for any commercial floor strike location where debris accumulation is a concern.

Browse the full manual flush bolts inventory at American Locksets. For the broader flush bolt catalog including automatic flush bolt options, see Ives flush bolts and coordinators and PDQ flush bolts and coordinators. For all door accessory and builders hardware, see builders hardware and the complete commercial locks catalog at American Locksets, trusted since 2001.

Frequently Asked Questions About Manual Flush Bolts

Q: What is a manual flush bolt?

A hand-operated bolt installed on the inactive leaf of a double door. Slides into a header strike at top and a floor strike at bottom to anchor the inactive door when not in use.

Q: What is the standard rod length on a manual flush bolt?

12 inches is standard for doors up to 7'-6" tall. Doors over 7'-6" require 18-inch rods. Specify rod length based on door height before ordering.

Q: What is the difference between manual, automatic, and constant latching flush bolts?

• Manual: Operated by hand every time

• Automatic: Bolts retract when active door opens, extend when it closes

• Constant latching: Inactive door stays latched until active door triggers release

Q: What ANSI standard covers manual flush bolts?

ANSI/BHMA A156.16. Manual flush bolts for metal doors are typically certified L04251. Wood door manual flush bolts are typically certified L04261.

Q: Are manual flush bolts UL fire rated?

Yes. Most commercial models including the Ives FB457, FB458, FB358, and PDQ 93170 are UL listed for 90-minute fire doors up to 8'-0" x 10'-0". Verify UL listing on the specific model before specifying on fire-rated openings.

Q: Do I need a dust proof strike with a manual flush bolt?

Recommended for any bottom floor strike. Dust proof strikes (Ives DP1/DP2) prevent debris from accumulating in the floor strike and blocking full bolt engagement.