Building frontage sounds simple — the width of the building facing the road — but in sign codes it is a defined term, and the definition decides how much sign area a tenant gets. Because the wall sign allowance formula almost always multiplies a per-foot ratio by frontage, getting the frontage number wrong throws off the entire permit. This entry breaks down the variants you will actually encounter.
The three frontage definitions
- Building frontage. The full width of the building wall along the street, regardless of how many tenants share it. Used when the sign allowance is computed for the whole structure.
- Tenant (lease) frontage. Only the width of the individual leased space along the street. This is the most common basis in multi-tenant retail, so each storefront gets an allowance proportional to its own width.
- Primary vs. secondary frontage. On corner lots, codes usually designate one street as the primary frontage (full allowance) and treat the side street as secondary (reduced or capped allowance).
What counts and what does not
Frontage is measured along the wall that faces a public street, not along a parking lot, an alley, or an interior mall corridor — unless the code specifically allows it. Recessed entries, angled facades, and wraparound corners create gray areas: some codes measure the straight-line width between the outermost building corners; others follow the actual wall plane. When the building steps in and out, that choice can swing the number by several feet.
Why the distance to the street is not frontage
A frequent mix-up: frontage is the width along the street, not the distance back from it. The distance from the building or sign to the property line is the setback, an entirely separate rule. Confusing the two leads people to plug a setback distance into a sign-area formula and come out wildly wrong.
Real-municipality example
In Charlotte, North Carolina, the Unified Development Ordinance ties attached-sign area to the width of the establishment’s frontage, and for a tenant on more than one street it addresses how each frontage contributes to the allowance. A corner drugstore there is measured on its primary street for the main allowance, with the secondary elevation handled under its own provision — so an installer who measures only the wider side, or who adds both frontages together as if they were one, will mis-size the sign. Pull the exact Charlotte section (or your city’s) and confirm which frontage definition applies.
Practical takeaway for installers
Before you touch a wall-sign quote, answer one question: whosefrontage does this code use — the building’s, the tenant’s, or a primary/secondary split — and how is it measured around corners and recesses? Once you have the correct linear-foot number, the wall sign allowance formula is straightforward arithmetic. FreeCodeChecks surfaces the frontage definition along with the multiplier so the math starts from the right input.