Sargent 351-B Mounting Plate — Low Ceiling Top Jamb Solution in EN (Aluminum) Finish

The Sargent 351-B Mounting Plate is a specialty adapter plate engineered for low ceiling top jamb mounting of the Sargent 351 Powerglide Series door closer. When standard top jamb clearance is insufficient, the 351-B solves the installation challenge by accommodating a minimum frame clearance of just 1-15/16 inches — making it the correct solution for tight soffit and low-ceiling conditions where the standard 351-A plate will not fit. This listing is supplied in EN finish (ANSI/BHMA 689 — aluminum powder coat), a neutral, corrosion-resistant coating that coordinates naturally with aluminum door frames and storefront applications.

The 351-B is non-handed — a single plate works for both left-hand and right-hand door swings, simplifying ordering and jobsite inventory. Order using the format: 351-B x EN.

Key Benefits

• Solves low-ceiling top jamb installations — minimum 1-15/16" frame clearance required, less than the 351-A plate
• Non-handed — one SKU covers both hand orientations; no field guesswork
• EN / ANSI 689 finish — durable aluminum powder coat resists corrosion and blends with aluminum frames
• Compatible with Sargent 351 Powerglide Series — designed as a factory-engineered accessory, not an aftermarket workaround
• Simplifies retrofit and new construction — drop-in plate adapts the 351 closer body to non-standard frame conditions without special fabrication

Typical Applications

• Commercial interior and exterior doors with low overhead clearance or shallow soffits
• Corridor and stairwell doors in buildings with drop ceilings where standard top jamb clearance is limited
• Retrofit projects replacing an existing closer in a space-constrained frame condition
• New construction openings specified with 351 Series closers where architectural conditions require top jamb mounting but ceiling height is restricted

Installation Note

The 351-B is specifically intended for top jamb mounting with low ceiling clearance. For standard top jamb or door-face mounting with 1-3/4" minimum frame clearance, the 351-A Mounting Plate is the appropriate selection. For parallel arm mounting on doors with narrow top rails, see the 351-D Drop Plate. Always verify frame clearance before specifying the mounting plate model.

Technical Details

The Sargent 351-B Mounting Plate in EN Finish is a heavy-duty door closer accessory specifically engineered to overcome the challenges of low ceiling applications. Designed for use with the Sargent 351 Series Powerglide® Door Closer, this plate is the industry-standard mechanical solution for Top Jamb (Push Side) mounting when overhead space is severely restricted. By providing a stable, reinforced mounting platform, the 351-B allows the closer body to be securely anchored to a frame with a minimum face of only 1-15/16" (49 mm), ensuring full hydraulic control without ceiling interference.

Finished in EN Sprayed Aluminum, this mounting plate is a critical structural solution for commercial and institutional environments where standard mounting patterns cannot be achieved. The non-handed design of the 351-B provides maximum field flexibility, allowing it to be used on both left-hand and right-hand doors. This plate is not merely a spacer; it is a performance-stabilizing solution that maintains the ANSI/BHMA Grade 1 integrity of the Sargent 351 series by ensuring the closer is mounted level and rigid, even on narrow-face frames in high-traffic schools, hospitals, and office buildings.

Structural Utility & ANSI Performance Summary

The 351-B Mounting Plate serves as a vital adapter between the door frame and the high-torque mechanics of a surface-mounted closer. Its function is essential for long-term safety and code compliance:

• Overhead Clearance Management: Engineered for "Top Jamb" applications where a standard mount would hit the ceiling or soffit.
• Narrow Frame Optimization: Distributes closing forces across a dedicated steel plate to prevent mounting screws from stripping out of narrow 1-15/16" frame faces.
• Hardware Lifecycle Extension: Prevents the closer body from "rocking" or vibrating, acting as a preventative maintenance solution that protects the door, frame, and internal closer seals.
• Certified Compatibility: When installed with a Sargent 351 Powerglide®, it supports the closer's ANSI/BHMA A156.4 Grade 1 certification—tested for over 2 million cycles—ensuring the opening remains compliant with Life Safety Codes and ADA requirements.

Technical Specifications

Engineered Solutions for Facility Maintenance

The Sargent 351-B EN addresses specific architectural hurdles faced by contractors and security professionals:

• Low Ceiling Correction: In many renovated spaces or older buildings, the ceiling height is too low for a standard Top Jamb mount. The 351-B is the primary architectural solution that allows the closer body to be mounted lower on the frame face while maintaining correct arm geometry.
• Storefront Frame Stabilization: Modern aluminum storefronts often have very narrow headers. This plate provides a secure anchoring solution, utilizing more surface area to ensure the closer remains rigid under high-wind or high-traffic conditions.
• Auxiliary Hardware Integration: This plate is a frequent clash-prevention solution when overhead auxiliary door holders or stops are present, providing the necessary clearance for all hardware to function independently.
• Aesthetic Uniformity: Because the plates are painted to match the closer, they provide a seamless design solution that blends into the frame, maintaining the clean lines of a professional commercial entryway.
• Simplified Field Retrofits: When upgrading from lighter-duty closers to the Powerglide® series, the 351-B acts as a retrofit solution, covering old mounting holes and providing a fresh, stable base for the new Grade 1 hardware.