Zoning is the system of local laws that divides land into districts and dictates what each district may be used for and how densely and tall it may be built. A zoning ordinance sets permitted uses, floor area ratio, height limits, setbacks, and parking, defining the legal envelope within which any commercial property can be developed or operated.
What Is Zoning?
Zoning is the local regulation that assigns each parcel to a district and specifies the uses and building form allowed there. Cities and counties enact a zoning ordinance and map that segment land into districts, each permitting some activities and prohibiting others, and each governing physical limits such as building height, density, and placement on the lot.
Two levers do most of the work. Use controls dictate what can operate on the site, retail, office, industrial, or residential, and dimensional controls dictate how much can be built. Floor area ratio, or FAR, caps total building floor area as a multiple of lot area: an FAR of 1.0 on a 10,000-square-foot lot permits 10,000 square feet of floor area regardless of the number of stories. Setbacks require minimum distances from property lines, and parking ratios set required stalls per unit of use.
Zoning control | What it limits |
Permitted use | Which activities may operate, such as retail or industrial |
Floor area ratio | Total floor area as a multiple of lot area |
Height limit | Maximum building height |
Setbacks | Minimum distance from structures to property lines |
Parking ratio | Required parking stalls per unit of use |
How Variances and Conditional Uses Work
A variance and a conditional use permit are the two ways to build or operate outside a district's default rules without rezoning. A variance is an approved deviation from a dimensional rule, such as a setback or height limit, granted only when strict enforcement would cause the owner an unnecessary hardship. A conditional use permit allows a use that is not automatically permitted but may be compatible under specified conditions.
Neither changes the underlying zoning designation. A variance excuses a specific dimensional requirement; a conditional use permit authorizes a specific use subject to conditions the board imposes. A separate category, the legal nonconforming use, protects a use that was lawful when established but no longer conforms to a later ordinance, allowing it to continue as grandfathered. Each requires local approval and carries entitlement risk and timeline that underwriting must price.
Why Zoning Matters
Zoning matters because it sets the legal ceiling on what a property can be, and that ceiling drives value more than the current building often does. A parcel zoned for an FAR of 3.0 can hold three times the floor area of one zoned 1.0, and floor area is what generates income. Buy the wrong use classification and the business plan is illegal on day one, regardless of price.
The underwriting discipline is to confirm zoning before the assumptions, not after. Highest and best use analysis rests on what zoning permits: an appraiser cannot credit a redevelopment that the code forbids. A deal that assumes a rezoning or variance is pricing an entitlement that may never come. The operator who verifies the zoning district, permitted uses, and dimensional limits during due diligence keeps a legal constraint from surfacing as a broken pro forma.
Example
Zoning turns lot size into buildable area through floor area ratio, and the math is direct. A developer is evaluating a 20,000-square-foot commercial lot in a district that permits an FAR of 2.0 with a 45-foot height limit. The FAR sets the maximum floor area independent of how the building is massed.
Item | Value |
Lot area | 20,000 sq ft |
Permitted FAR | 2.0 |
Maximum floor area | 20,000 x 2.0 = 40,000 sq ft |
At 10,000 sq ft per floor | 4 stories within the height limit |
The FAR allows 40,000 square feet of floor area. Built at 10,000 square feet per floor, that is four stories, which the 45-foot height limit accommodates. If the developer's plan called for 60,000 square feet, the code forbids it without a variance or rezoning, and the pro forma built on that assumption is invalid. Confirming the FAR first sizes the deal correctly; assuming it last invites a rejected permit.
Variations and Edge Cases
Zoning behaves differently across district types and relief mechanisms. The variants below show where the standard framework bends.
Variant | Treatment |
Euclidean zoning | Traditional single-use districts separating residential, commercial, industrial |
Form-based code | Regulates building form and streetscape more than use |
Overlay district | Adds rules on top of the base zoning, such as historic or flood overlays |
Planned unit development | Negotiated site-specific standards replacing base zoning |
Legal nonconforming use | A once-lawful use grandfathered after the ordinance changed |
Zoning vs Deed Restrictions
Zoning is often confused with deed restrictions, and both limit how land is used, but the source differs. Zoning is public law enacted and enforced by a city or county, applying to every parcel in a district and changeable through the government process. A deed restriction, or restrictive covenant, is a private contractual limit written into the deed and enforced by other private parties who benefit from it.
Zoning is public and uniform across a district; deed restrictions are private and parcel-specific. A property must satisfy both. A use can be permitted by zoning yet barred by a recorded covenant, such as a no-competing-use restriction, and the private restriction controls even where the code would allow it. Due diligence checks the zoning ordinance and the recorded deed restrictions separately, because clearing one does not clear the other.
Frequently Asked Questions
What is zoning in commercial real estate?Zoning is the system of local laws that divides land into districts and dictates what each may be used for and how densely and tall it may be built. A zoning ordinance sets permitted uses, floor area ratio, height limits, setbacks, and parking, defining the legal envelope for any commercial property.
What is the difference between a variance and a conditional use permit?A variance is an approved deviation from a dimensional rule, such as a setback or height limit, granted only when strict enforcement causes the owner unnecessary hardship. A conditional use permit authorizes a use not automatically permitted but allowed under specified conditions. Neither changes the underlying zoning designation.
How does floor area ratio work in zoning?Floor area ratio, or FAR, caps a building's total floor area as a multiple of lot area. An FAR of 2.0 on a 20,000-square-foot lot permits 40,000 square feet of floor area regardless of the number of stories, subject to height and setback limits. FAR is a primary driver of a parcel's development value.
Related Terms
ALTA Survey
Easement
Highest and Best Use
Due Diligence
Mixed-Use Development