Building frontage is the length of wall your code counts when it works out your sign allowance. Codes disagree about which wall counts: the whole building, just your tenant space, or only a wall facing a street. Get that answer before you calculate anything.
How one real code handles it
Monterey, California defines the term in its sign chapter, section 31-10:
“The horizontal distance along a building face that is oriented in parallel to a public right-of-way or public walkway, not including the Monterey Peninsula Recreational Trail. For purposes of this definition, a public walkway is a path leading to a business entrance.”
Two things stand out. First, a “building face” has its own definition: a vertical wall surface, windows included, at least ten feet wide and eight feet tall that forms a distinct outside edge of the building. A wall segment narrower than ten feet fails that test, and windows count as part of the wall. Second, the wall does not have to face a street. By the definition's wording, a wall running along the path to a business entrance counts too. The same section defines “lot frontage” separately, as distance along a lot line next to a public street, so do not swap one for the other. (Section history includes Ord. 3715, 2025. We read it on September 28, 2026.)
Label the input on the plan
- Whole building, one tenant space, or another defined frontage?
- Which walls qualify: street side, parking side, walkway side?
- Does the measurement follow a recessed or angled wall, or run straight across?
- Are several frontages added together, kept separate, or capped overall?
On a made-up building 100 feet wide with a 25-foot tenant space, the two possible inputs differ by a factor of four. Neither is right until the code says which one it means. Keep the measured line and the calculation on the same drawing, then continue with the wall-sign formula. For distances to a boundary, use the setback guide.