●Academy · Reference
Zoning Glossary
Planning codes are written in their own language. This glossary translates the terms that decide what you can build — FAR, setbacks, coverage, overlays, variances, and the rest — into plain English, with why each one matters to a development decision.
Every term below is really a rule about this parcel.
The anatomy of a zoning envelope
R-3 · illustrative parcel
Plan view · setbacks & coverage
Setback line
Buildable footprint
Section view · height & FAR
Buildable mass
Height limit
FAR
Setback
Lot coverage
Height limit
Stepback
Buildable envelope
One lot, every term in context — the rules below combine to define what fits inside the buildable envelope.
The four terms that shape every site
Before the full glossary, here are the big four — drawn on a parcel so you can see exactly what each one limits.
Floor Area Ratio
Total floor area ÷ lot area. The master dial for how much building you get.
Setback
Required gap from each lot line — front, sides, rear — that shrinks your footprint.
Lot Coverage
The max share of the lot buildings may cover — pushing you to build up, not out.
Height Limit
The ceiling on building height — with FAR, it sets how many floors you can stack.
Zoning & use
- Zoning
- The system of local laws that divides land into districts and sets the rules for what can be built and how it can be used in each one.
- Permitted (By-Right) Use
- A use the zoning allows automatically, without needing discretionary approval from the city.
- Conditional Use CUP
- A use allowed in a zone only with special approval and conditions attached to manage its impact on neighbors.
- Nonconforming Use
- A use or building that was legal when built but no longer complies with current zoning, usually allowed to continue but not expand.
- Mixed-Use
- Zoning or a building that combines more than one use, such as ground-floor retail with apartments above.
Why it matters: It is the first thing to check on any site — it decides whether your idea is even legal before you spend a dollar.
Why it matters: By-right projects are faster, cheaper, and far less risky than ones that need a hearing.
Why it matters: It adds time, cost, and uncertainty — budget for the approval process, not just construction.
Why it matters: It can limit renovations and complicate financing, so confirm its status early.
Why it matters: It can unlock more value and is increasingly favored by cities — but it complicates financing and management.
Form & dimensions
- Floor Area Ratio FAR
- The ratio of a building’s total floor area to the lot area. A FAR of 2.0 on a 5,000 sf lot allows 10,000 sf of building.
- Setback
- The minimum required distance between a building and each lot line, defined separately for the front, sides, and rear.
- Lot Coverage
- The maximum share of a lot that buildings may cover, given as a percentage of total lot area.
- Height Limit
- The maximum building height allowed in a zone, expressed in feet, meters, or number of stories.
- Buildable Envelope
- The three-dimensional space a building may legally occupy after setbacks, height, and coverage are applied to the lot.
- Stepback
- A required recess of a building’s upper floors back from the lower facade to reduce visual bulk and protect light and air.
- Gross Floor Area GFA
- The total enclosed floor area of a building, the basis for FAR and many development fees.
Why it matters: It is the master dial for how much you can build — and therefore for value. Always find it first.
Why it matters: Setbacks shrink the footprint you can actually build, often well below what the lot size suggests.
Why it matters: Combined with setbacks, it caps your footprint and pushes you to build up rather than out.
Why it matters: Together with FAR it determines how many floors — and units — you can stack on the buildable footprint.
Why it matters: This is the real container for your project — design and yield must fit inside it.
Why it matters: It can cut usable area on upper floors and reshape your unit layouts.
Why it matters: How GFA is measured (what counts and what is exempt) can meaningfully change your allowable size.
Density & incentives
- Density
- The number of dwelling units allowed per unit of land, often expressed as units per acre or units per lot.
- Density Bonus
- Additional allowable density granted in exchange for a public benefit such as affordable housing or open space.
- Inclusionary Zoning
- A rule requiring a share of new units to be affordable, sometimes paired with a density bonus to offset the cost.
- Transfer of Development Rights TDR
- A mechanism that lets unused development capacity be sold from one parcel and added to another.
Why it matters: It is the cap on how many units you can sell or rent — the core driver of residential value.
Why it matters: It can materially increase yield and returns — often the difference between a deal that pencils and one that does not.
Why it matters: It changes your unit economics; model it from the start, not as an afterthought.
Why it matters: It can let you build more than base zoning allows — a potential source of extra value or cost.
Process & approvals
- Entitlement
- The full set of government approvals that grant the legal right to develop a property as proposed.
- Rezoning
- A formal change to a property’s zoning designation, altering what can be built there.
- Variance
- Permission to deviate from a specific zoning standard because strict application would create an undue hardship unique to the property.
- Site Plan Review
- The process by which a city reviews a proposed development’s layout, access, landscaping, and design for compliance.
- Subdivision
- The legal division of a parcel into two or more lots for sale or separate development.
Why it matters: Entitled land is worth far more than raw land — getting entitlements is where much value is created and risk lives.
Why it matters: It can unlock huge upside but is slow, political, and uncertain — treat it as a project of its own.
Why it matters: A variance can rescue an awkward lot, but approval is discretionary and never guaranteed.
Why it matters: It is a common gate even for by-right projects — plan for the time and possible revisions.
Why it matters: Splitting a lot can multiply value, but it triggers its own approvals, surveys, and infrastructure rules.
Land & legal
- Accessory Dwelling Unit ADU
- A secondary, self-contained home on the same lot as a primary residence — a backyard cottage, garage conversion, or basement suite.
- Easement
- A legal right for another party to use part of a property for a defined purpose, such as utility lines or access.
- Lot Line & Frontage
- Lot lines are a parcel’s legal boundaries; frontage is the length of lot line along a public street.
- Impervious Surface
- Any hard surface — roofs, driveways, patios — that water cannot pass through, often capped by code.
- Plat
- An official recorded map showing the division, dimensions, and boundaries of lots within a subdivision.
Why it matters: Often the lowest-risk way to add a unit and income, increasingly allowed by-right.
Why it matters: An easement can block where you build — always check title before you design.
Why it matters: Setbacks reference lot lines, and minimum frontage rules can determine whether a lot is even developable.
Why it matters: Impervious-surface limits can constrain parking and building area, especially in flood-sensitive areas.
Why it matters: The plat governs your legal lot configuration; amending it is a formal process.
Economics & analysis
- Highest and Best Use HBU
- The use that is legally permissible, physically possible, and financially feasible, and that produces the highest value for a site.
- Yield
- The amount of developable product — units or buildable square feet — a site can produce under its rules.
- Pro Forma
- A financial model projecting a project’s costs, revenue, and returns over time.
- Overlay
- An extra regulatory layer placed on top of base zoning to address a specific concern — historic, environmental, or design.
Why it matters: It is the question every analysis should answer before you commit to a scheme.
Why it matters: Yield drives revenue; a small change in FAR or unit size can swing a deal’s viability.
Why it matters: It is the document that says yes or no — and the one lenders and partners scrutinize.
Why it matters: Overlays can add requirements that base zoning hides; miss one and your plan may be non-compliant.
Stop looking them up — see them on your lot
UnlockLand reads these rules off your parcel automatically, so FAR, setbacks, and coverage become a buildable envelope instead of a vocabulary test.
Zoning Intelligence
See FAR, setbacks, coverage, and overlays for your parcel in plain language.
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Development Potential
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