A blade sign is a sign mounted perpendicular to a building facade, wall, or support post. These are almost always double-sided and are designed to be seen by pedestrian and vehicular traffic moving parallel to the building. They are common on retail storefronts and urban corridors, providing clear visibility where a flat wall sign would go unnoticed.
Construction and Mounting
Blade signs are manufactured as double-faced assemblies using materials like aluminum, high-density urethane (HDU), wood, or acrylic. Because the perpendicular mount creates a lever arm that amplifies wind load and dead weight, structural connection is required.
Standard practice and building codes prohibit anchoring into masonry veneer, stucco, or drywall alone. Installers use welded steel brackets, architectural cantilevered arms, or overhead hanging brackets. These mounts require through-bolting to structural wall framing or heavy masonry anchors.
Types of Blade Signs
Manufacturers build blade signs in several styles based on local codes and client preferences.
- Non-illuminated: Features flat-cut metal, carved HDU, or painted panels.
- Externally illuminated: Lit by gooseneck fixtures or architectural spotlights aimed at the sign faces.
- Internally illuminated: Contains internal LEDs within a cabinet, push-through acrylic lettering, or edge-lit faces.
- Mounting styles: Built to remain rigidly fixed in place or designed to hang and swing from an overhead bracket.
What Affects Cost
The price of a blade sign varies based on several factors.
- Illumination method: Internal LEDs, external lighting, or non-lit designs.
- Bracket complexity: Custom architectural brackets require more fabrication time than standard mounts.
- Double-sided finishing: Creating graphics and finishes for two faces increases material and labor requirements.
- Engineering and permits: Structural engineering requirements and municipal encroachment fees add to the total, and ignoring these rules is often why sign permits get rejected.
- Installation access: Requiring a bucket truck instead of a standard ladder impacts installation time and equipment needs.
Sign codes change and vary by zoning district and overlay. Confirm with the authority having jurisdiction before submitting a permit.
Frequently Asked Questions
What is the difference between a blade sign and a projecting sign?
In building and zoning codes, the terms are often used interchangeably. In trade practice, a blade sign specifically denotes a compact, projecting format common to retail storefronts. This distinguishes it from large structural marquees or fascia signs that mount flat against a wall.
What is the minimum clearance needed above a sidewalk?
Signs extending over pedestrian paths generally require a minimum vertical clearance of 8 to 9 feet from the ground to the bottom of the sign. Clearance over driveways or alleys typically requires a 14-foot minimum. These rules vary strictly by local municipal code.
Can a blade sign hang over a public sidewalk?
Yes, but extending a sign over a public right-of-way enters municipal airspace. This almost universally requires a specialized encroachment permit as part of the sign permit process and proof of commercial general liability insurance. The allowable projection distance varies strictly by municipality.
How do sign companies show clients what a blade sign will look like?
Vuely is AI sales software for sign companies. A rep visits a customer's site, captures a survey with photos and measurements, and Vuely generates a photo-accurate mockup of the sign on the customer's actual building, checks the design against the local city sign code, estimates price, and collects a signature before the rep leaves.
Do I need an engineer’s stamp to permit a blade sign?
Many municipalities require a licensed engineer’s calculation and stamp for perpendicular signs because of the added wind load and dead weight. This requirement depends heavily on how you calculate sign area and the exact rules of the local jurisdiction.
Vuely is AI sales software for sign companies: site surveys, mockups on the customer's own building, and sign code checks before the quote goes out.