What is a site plan used for?

A site plan is used for reviewing building permit applications, verifying setbacks and zoning compliance, confirming where new work will be located on the property, understanding access points, driveways, and parking, and identifying potential site constraints such as easements, drainage, or protected areas.

What does a site plan include?

A site plan typically includes property boundary lines, street frontage and neighboring lots for context, existing buildings and major site features, proposed structures or improvements, distances from structures to property lines, labeled setbacks, driveways, access paths, or parking, and a north arrow with written scale.

When is a site plan required?

A site plan is typically required for fences, walls, and gates; decks, patios, and outdoor structures; sheds and accessory structures; pools and hardscape work; additions, new construction, and major remodels; retaining walls or projects on sloped terrain; and tree removal in jurisdictions that regulate protected trees.

Is a site plan the same as a survey?

No, a site plan is not the same as a survey. A survey is prepared by a licensed professional and may be required in some situations. A site plan often uses boundary information but is not always a substitute for a survey when one is required.

How detailed does a site plan need to be?

The level of detail depends on the project and the local building department. Simple residential permits often require a straightforward plan showing boundaries, structures, setbacks, and dimensions. Larger projects may require additional details such as grading, drainage features, or expanded site context.

What Is a Site Plan?

A site plan is a scaled drawing that shows the layout of a property, including property boundaries, existing structures, and proposed improvements. Building departments use site plans to understand where work is located on a lot and how it relates to property lines, setbacks, access, and other site constraints.

A site plan is a scaled, bird's-eye drawing of a property that shows the location of structures, boundaries, setbacks, driveways, and other site features in relation to one another. Unlike a floor plan — which maps the interior layout of a building — a site plan focuses entirely on what exists on the land itself. It is also distinct from a property survey: while a survey establishes legal boundary lines and is typically prepared by a licensed surveyor, a site plan uses those boundary lines as a framework to show how a proposed or existing improvement fits within the lot. Homeowners, contractors, and developers most often need a site plan when applying for a building permit, and the document must be drawn to scale and include specific measurements to be accepted by a building department. If you are planning a structural addition, you may also want to review guidance on construction permit site plans to understand what reviewers expect.

What Building Departments Typically Require on a Site Plan

Most jurisdictions require a site plan as part of any permit application involving new construction, additions, accessory structures, pools, fences, or significant grading. The International Code Council provides model codes that most U.S. municipalities adopt, and those codes consistently require applicants to demonstrate that proposed work complies with local zoning setbacks, lot coverage limits, and easement restrictions before a permit can be issued.

A code-compliant site plan generally includes:

Property boundary lines with dimensions and north arrow
All existing and proposed structures, labeled and dimensioned
Setback distances from each structure to every property line
Driveways, walkways, and points of access to the street
Easements, utility lines, and any flood zone designations
Scale bar and lot area calculation

Some counties also require impervious surface calculations to ensure stormwater runoff stays within allowable limits — a threshold that the EPA's stormwater program increasingly influences at the local level.

Common Mistakes and Practical Tips for First-Time Applicants

One of the most frequent reasons permit applications are rejected is a site plan that is either not drawn to scale or is missing setback dimensions. Building reviewers need to verify — at a glance — that your proposed structure does not encroach into a required setback or easement. Submitting a rough sketch or a plan without a scale bar will almost always result in a correction notice and added delay.

Always base your site plan on your recorded property survey — do not estimate boundary locations
Show both existing and proposed conditions clearly labeled, especially if you are adding to an existing structure
Check your local zoning ordinance for lot coverage maximums before designing your project — many residential zones cap impervious coverage at 30–40% of lot area
Confirm whether your jurisdiction requires a licensed professional's stamp or accepts owner-prepared drawings

If your project involves an accessory structure like a garage or studio, the same site plan principles apply — see the shed and outbuilding site plans page for project-specific guidance. The HUD zoning resource library is also a useful reference for understanding how local zoning interacts with federal housing programs.