Security bars for duct openings
Security Bars / Burglar Bars
Custom fabricated security bar assemblies for duct openings, roof curbs, wall penetrations, and high-security HVAC applications.
- Used to discourage people, animals, or large debris from entering duct systems through exposed rooftop or wall openings.
- Typically built with a steel perimeter frame and 1/2" rods welded at 6" on center, with custom spacing available when quoted.
- Most often shipped loose for installation into roof curbs, curb adapters, wall penetrations, or duct openings by others.
MaterialMild Steel
Rod layout1/2" at 6" O.C.
FinishRaw / optional coating
Construction Standard
| Application | Security bar assemblies for high-security duct openings, roof curbs, wall penetrations, equipment openings, and exposed HVAC intake or exhaust locations. |
| Standard material | Mild steel is standard. Stainless steel and aluminum can be quoted when corrosion resistance, weight, or project requirements call for alternate material. |
| Frame options | Frames can be fabricated from flat bar, angle, or sheet metal to match the opening, installation method, and required bearing surface. |
| Rod layout | 1/2" rods at 6" on center are standard. Rod spacing, direction, clear opening, and frame depth should be confirmed before release. |
| Welding | Ends, corners, rod intersections, and frame joints are MIG welded for a rigid welded assembly unless another weld process is quoted. |
| Finish | Security bars are typically supplied raw/uncoated. Paint, powder coating, galvanizing, heat treating, or case hardening can be quoted when required. |
| Quality check | Security bar assemblies receive visual inspection before release. Code, security rating, structural approval, and field installation are by others unless quoted. |
Build Quality
Made to specBuilt to released opening size, frame type, and rod layout.
Built toughWelded bar construction for exposed security openings.
Quality checkedWelds and frame fit receive visual inspection before release.
Opening readyShipped loose for field installation in curbs or penetrations.
Fabrication Capabilities
| Bar assemblies | Rectangular security bars, curb burglar bars, wall penetration bars, duct opening bars, equipment opening bars, and special frame sizes. |
| Frame styles | Flat bar frames, angle frames, sheet metal frames, flanged frames, drop-in frames, and custom mounting faces when shown or quoted. |
| Rod layouts | Standard 1/2" rods at 6" on center, custom rod spacing, cross-bar layouts, divided panels, and reinforced sections. |
| Materials | Mild steel standard, with stainless steel or aluminum options available when quoted. |
| Security details | Heat treating, case hardening, finish coating, bird screen, and special installation hardware can be coordinated when specified. |
| Release support | Built from released dimensions, templates, sketches, field measurements, or drawing packages with installation responsibilities clearly identified. |
Build Options
Standard rod1/2" round rods are standard for burglar bar assemblies unless another rod size is quoted.
Frame typeFlat bar, angle, or sheet metal frames can be selected to match the opening and attachment method.
Finish optionsRaw steel is standard. Paint, powder coating, galvanizing, stainless steel, or aluminum can be quoted.
Bird screenBird screen can be added over the bar assembly when the opening also needs pest or debris control.
Configuration Options
Flat bar
Low profileSimple welded perimeter frame for many duct and curb openings.
Angle
Mounting edgeAngle frames provide a stronger mounting face where the opening needs it.
Sheet metal
Integrated frameFormed frames can coordinate with curb, adapter, or duct construction.
Screen
Bird screenOptional screen can be added when pest control is part of the scope.
Optional Accessories
Bird screenWire screen can be added over the bar grid for pest or debris control.
CoatingsPaint, powder coating, galvanizing, or special coating requirements where quoted.
HardeningHeat treating or case hardening can be quoted when the project requires it.
Custom detailsMounting tabs, drilled holes, labels, piece marks, shipping splits, and special hardware.
Required for Quote / Release
- Opening width, length, quantity, frame type, and required clear opening or outside frame dimensions.
- Approved drawing, sketch, curb/duct opening detail, wall penetration detail, or verified field dimensions.
- Rod size, rod spacing, rod direction, bird screen requirement, and whether the assembly ships loose or installs into another product.
- Material, finish, coating, galvanizing, powder coating, hardening, stainless, or aluminum requirements.
- Mounting face, hardware, drilled holes, piece marks, shipping splits, and inspection requirements.
Not Included Unless Quoted
- Installation, field welding, anchoring, fastening, roofing, wall penetration work, or field modifications unless quoted.
- Engineering, security rating, detention rating, permits, inspections, AHJ approval, or listed-system certification.
- Hardware, coatings, galvanizing, heat treating, bird screen, field measuring, or rework from changed release dimensions unless quoted.
Scope & Responsibility
Code note: Security bar and burglar bar assemblies may be governed by project specifications, security requirements, mechanical code, local code, building code, and AHJ direction. Empire fabricates the bar assembly to released dimensions and quoted scope; final security requirement, code interpretation, structural approval, installation method, anchorage, and field acceptance remain the responsibility of others unless expressly included.
Ready to Quote?
Let's get your duct package moving.
Send drawings, sketches, photos, or field measurements. Empire is ready to go to work for you.
quotes@empiremetalproducts.com
602-424-9980