How to Make a Site Plan: A Permit-Ready Step-by-Step Guide

To create a site plan, you do four things in order: confirm what your local permit office requires, gather verified property data, draw the parcel to scale showing property boundaries, setbacks, existing structures and utilities, then overlay the proposed work with dimensions. A site plan is a map of your property seen from above, and most construction permits, zoning reviews and contractor bids depend on one. This guide is for homeowners planning a deck, shed, addition, pool or ADU, for contractors who would rather not outsource every small site plan drawing, and for small developers testing what fits on a site. Drawing rectangles is the easy part. The hard part is knowing which lines are legal property boundaries, which dimensions are verified, and which rules apply to the property today. Local authorities always control.

What Is a Site Plan?

A site plan is a scaled, top-down drawing of an entire property: boundaries, existing structures, driveways and access, topography, drainage, landscape features and whatever you propose to build. Nearly all site plans are two-dimensional. Reviewers use them to answer one question fast: does the project fit within the rules that apply to this parcel? For the owner, the same sheet doubles as the backbone of project planning, because it forces every assumption about space, access and utilities into measurable form.

Site Plan vs. Floor Plans vs. Property Survey

Document	What it shows	Who prepares it
Site plan (plot plan)	The whole property from above: property boundaries, structures, access, drainage, landscape elements	Owner, designer, contractor or engineer, depending on scope
Floor plans	The interior layout of one building: rooms, walls and their dimensions	Designer or architect
Property survey	A licensed surveyor's legal measurement of property boundaries and monuments	Licensed land surveyor only

"Plot plan" is simply the term many residential permit counters use for the same architectural document. A site plan is often built on top of a survey. It is never a substitute for one, and neither document replaces the floor plans, elevations and structural sheets that complete a permit set.

The Three Levels: Concept, Permit Ready Site Plan, and Civil

A concept site plan is a feasibility sketch you use to see whether a deck or ADU might fit on the site. A permit ready site plan is drawn to the jurisdiction's checklist with verified dimensions and compliance data. A civil or construction site plan adds grading, drainage, utility design, erosion control, fire access and accessible routes, usually with an engineer's involvement. An aerial image with arrows drawn on it belongs in the first category, not the second, and submitting one where permit ready plans are expected is a guaranteed correction notice.

When Is a Site Plan Required?

Building permits, zoning and land-use applications, health department review for septic and wells, fire access review, and contractor pricing all commonly require site plans. The 2024 International Residential Code sets the national baseline in R106.2: show the size and location of new construction and existing structures, their distances from lot lines, and for demolition work, what is being removed and what remains. Local adoption and amendments go further, often much further, and some permits that seem minor still trigger a full site plan submittal.

Check Local Requirements Before You Create a Site Plan

Download your jurisdiction's current site plan checklist before you touch graph paper or software. It dictates sheet size, scale, required content and file format, and those specifics vary enough that plans drawn for one city get corrected in the next one over. Many counters also expect a vicinity map on the first sheet showing where the property sits in relation to nearby streets.

Requirements also move. Seattle's SDCI Tip 103 site-plan guidance was revised on August 20, 2025, and the city notes that some published guidance can lag behind recent state-mandated code changes. Permanent Seattle residential zoning changes took effect January 21, 2026. Guidance printed a year ago may already be wrong, and stale zoning data is one of the cheapest mistakes to avoid.

Which Departments to Check

• Building department (permit submittal standards)
• Planning or zoning (setbacks, coverage, overlays)
• Public works or transportation (right-of-way, driveway approach, curb cuts)
• Water, sewer and stormwater utility districts
• Fire department (access, turnarounds, hydrant distance)
• Environmental or critical-areas staff
• County health (septic systems and wells)

Private rules run in parallel with public ones. HOA requirements can add their own setbacks, height limits, materials review and approval timelines, and an architectural committee usually wants to see the same sheet the city does.

What to Confirm Before Drawing a Line

Your zoning district and any overlays, front, side and rear setbacks, height limits, lot coverage and floor area ratio caps, tree protection rules, critical-area buffers, whether owner-prepared plans are accepted at all, and the required sheet size, scale and submission format. If the portal requires a registered account to upload plans, set that up early so a file size or format surprise does not cost you a day.

Gather Reliable Property Data and Documents

Accurate measurements are what make a site plan usable. Before drawing, collect the documents that establish where things actually are, then be honest with yourself about how solid each data source is. Pull the property's collection of recorded paperwork in one sitting, because preparing documents halfway through a drawing is how easements get missed.

Source Documents Worth Collecting

• Recorded boundary survey and recorded plat
• Deed and title report (this is where easements hide)
• Previously approved permit plans for the property
• Septic and well records
• Utility as-builts and service records
• Topographic survey, if one exists
• Assessor maps and county GIS records
• FEMA flood maps
• Your own current field measurements

Rate Every Input: Verified, Official Reference, Approximate, Proposed

Confidence level	Sources	How to use it
Verified	Recorded survey, approved permit plans, field survey	Safe to dimension from
Official reference	Zoning map, FEMA map, utility or permit record	Reliable for rules, not for exact locations
Approximate	Assessor map, GIS data, aerial image, tape measurement	Research only; verify before relying on it
Proposed	New work not yet built	Label clearly as proposed

Bellevue states plainly that aerial photographs are not acceptable site plans, and requires applicants to verify property boundaries, rights-of-way, setbacks and easements. Treat that as the general standard, not a local quirk.

Do You Need a Surveyor, or Can You Create a DIY Site Plan?

Yes, a property owner can often prepare simple site plans themselves, provided property boundaries are well documented and the jurisdiction accepts owner-prepared plans. Acceptance depends on the scope of work, how certain the property lines are, and whether stamped professional site plans are required for that permit type. A shed replacement on a rectangular platted lot is a different problem from an addition three feet off a side yard line.

Signs You Should Hire a Licensed Land Surveyor

• You cannot locate the property corners or monuments
• The project sits close to a setback line or lot line
• A fence, driveway or structure may encroach
• The site is irregular in shape or steeply sloped
• You are creating a new boundary or subdividing
• Recorded documents conflict with each other
• The building official asks for certification

Seattle's residential code, for example, lets the building official require a Washington-licensed land surveyor where work may intrude into required open space or across a property line. That authority exists in most jurisdictions in some form, and the cost of a boundary survey is usually smaller than the cost of moving a foundation. A surveyor's site visit also settles arguments that recorded paperwork alone cannot, since monuments in the ground beat assumptions on a screen.

Choose a Scale and Set Up the Site Plan Drawing

Most residential site plans are drawn at 1 inch = 20 feet, and 1 inch = 30 feet shows up on larger parcels. Neither is a national rule.

What Scale Should a Residential Site Plan Be?

The permitting authority decides. Portland requires residential site plans at 1 inch = 10 feet or larger. King County treats 1 inch = 20 feet as its standard engineering scale while accepting another standard engineering scale if the property stays legible. Bellevue commonly accepts 1 inch = 10 feet or 1 inch = 20 feet. Pick a scale that fits the entire parcel on the sheet with room left for dimensions, notes and a calculations table, then confirm it against the checklist.

Sheet Setup: North Arrow, Graphic Scale, Vicinity Map, Legend and Title Block

Every sheet needs a north arrow and both a written scale and a graphic scale bar. The bar matters because printed and scanned plans get resized, and a "1 inch = 20 feet" note becomes a lie the moment someone prints to a different paper size. Add a legend explaining your line types, a small vicinity map orienting the reviewer to the surrounding streets, and a title block carrying the property address, parcel number, owner, plan preparer, drawing date and revision dates. Multi-sheet submittals often open with a title page that repeats the same property information alongside a sheet index.

How to Draw the Existing Site

Work outward from the legal boundary. Each step below builds on the one before it.

Step 1: Plot Property Lines and Rights-of-Way

Plot each boundary length and bearing from the best data you have, usually the recorded survey or plat. Then add adjacent street and alley names, right-of-way width, and the sidewalk, curb and planting strip. The classic homeowner mistake is measuring to the fence, curb or sidewalk instead of the legal property boundaries. Fences drift. The right-of-way often extends well past the curb into what looks like your front lawn.

Step 2: Show Setbacks, Easements and Buffers

Draw front, side and rear setback lines as dashed offsets from the property boundaries. What is left inside them is your buildable envelope. Add recorded easements, building restriction lines, overlay boundaries, critical-area buffers, and floodplain or floodway lines where they apply. Easements are the single most commonly omitted item on homeowner-drawn plans, and a utility easement running under a proposed foundation will stop a permit cold.

Step 3: Add Existing Structures, Hardscape and Landscape Elements

Draw the house footprint and everything else on the site: accessory structures, decks, porches, steps, patios, pools, sheds, retaining walls and rockeries, driveways, parking areas and curb cuts. Show roof overhangs and projections as dashed lines. Include protected trees and planting beds, plus the well, septic tank and drain field if the property has them.

Step 4: Show Utilities, Drainage and Topography

Map existing water, sewer, storm, gas and electric connections, along with contours, spot elevations and drainage features like swales and downspout discharge points. An 811 locate is a pre-excavation safety step, not a data source: it marks the approximate positions of participating operators' facilities, may not include privately owned utility lines, and does not replace utility as-builts or a boundary survey.

Add the Proposed Work to Create a Permit-Ready Site Plan

Reviewers are not grading your linework. They are checking relationships: how far the new thing sits from every property line, how the site drains, where the utilities connect, whether the proposed changes add up numerically.

Dimension Everything to the Property Lines

Give the proposed footprint its overall dimensions, then add perpendicular distances from the nearest part of each structure to each lot line and to other structures on the property. If your jurisdiction measures setbacks from eaves or projections rather than the wall face, dimension from those.

Distinguish Existing to Remain, To Be Removed, and Proposed

Use three distinct line types and define them in the legend so existing and proposed conditions read clearly at a glance. The 2024 IRC specifically requires demolition plans to identify both what is being removed and the existing structures that remain, which is exactly the distinction reviewers look for on additions and rebuilds. If the footprint shifts during review, issue a new site plan rather than penciling a correction onto the approved sheet.

Run the Numbers: Lot Coverage, Impervious Surface and Parking

Where the code applies them, calculate and tabulate lot coverage, impervious surface, floor area ratio, landscaped or open space, parking counts, total disturbed area, cut and fill volumes, and tree credits or replacement requirements. Put the table on the sheet so the reviewer does not have to derive it from your dimensions.

Apply the Plans to the Project: An ADU Example

An accessory dwelling unit is where a site plan stops being paperwork and starts being a feasibility test.

Testing the Buildable Envelope

Subtract setbacks, easements, tree protection zones and any critical-area buffers from the parcel, then look at the rectangle that survives. Building placement inside that rectangle still has to satisfy required separation from the main house, height limits under any rear-yard restrictions, and whether the unit pushes lot coverage past its cap. Plenty of sites that look big enough are not, once the buffers are drawn to scale.

Access, Utilities and Trees Often Decide Feasibility

Sewer and water tie-in routes, electrical service capacity, fire access and the path from the street to the unit's entrance, parking, drainage and protected trees can each kill an otherwise legal footprint. For an ADU, the site plan effectively becomes a feasibility study: Seattle homeowners can compare current municipal guidance with a local design-build resource such as https://seattlemodernbuildings.com/ when evaluating how setbacks, utility routes, access, trees and the buildable envelope interact on their property.

Grading, Drainage, Retaining Walls and Hazard Overlays

Some sites force the plans to escalate from a simple parcel diagram to something closer to a civil set.

Sloped Sites: Contours, Spot Elevations and Retaining Walls

Show existing and proposed contours, spot elevations at key points, top and bottom of wall elevations, proposed finished floor elevations, and cut and fill quantities. Retaining walls above a certain height trigger separate structural review and engineering in most jurisdictions, so check the threshold before you assume the wall rides along with the building permit.

Flood Zones, Erosion Control and Environmental Rules

In mapped flood hazard areas, show the FEMA floodplain and floodway boundaries, the design flood elevation and the proposed lowest-floor elevation. Federal construction stormwater permitting under the Clean Water Act generally applies once you disturb one acre or more, including smaller sites that are part of a common plan of development totaling at least an acre. State and local thresholds are often stricter. On unsewered property, show the septic tank, primary and reserve drain fields and the well protection radius.

Accessible Routes for Commercial and Public Projects

For covered facilities, accessible routes must connect site arrival points to accessible entrances. That means accessible parking spaces, passenger loading zones, public sidewalks and transit stops, per U.S. Access Board guidance. Draw the route on the plans, do not just note it.

Special Cases: Repairs, Additions and Reconstruction

Damage repair projects are the hardest case for existing-versus-proposed clarity. You may be dealing with partial demolition, salvageable structures, capped or disconnected utilities, temporary construction access, and engineering reports submitted alongside the site plan.

Documenting Damaged, Demolished and Remaining Conditions

After major fire damage, the plans should identify structures and site features that will remain, areas to be demolished, utility conditions and the proposed reconstruction footprint; a restoration and reconstruction specialist such as Golden Coast Construction & Restoration may use that data to coordinate the repair scope with engineers, insurance companies and local authorities. Structurally damaged property frequently requires additional construction details and an engineer's report under local emergency-repair guidance, so ask what the reviewer expects before assembling the submittal.

Tools: Site Plan Templates, Software and When to Hire Out

Hand Drawing, Annotation Tools and a Site Plan Creator

Graph paper and an engineer's scale still produce accepted permit plans for simple property. Digital options run from free site plan templates in Canva and general annotation tools, to a dedicated site plan creator such as SitePlanCreator that advertises permit-ready plans in under ten minutes, up to full CAD packages, which are powerful tools with a real learning curve. Most of these tools ask you to create an account, import parcel data or a base image, then trace and dimension over it. No site plan creator verifies your property boundaries. Output quality equals input quality, and a beautifully rendered plan built on an assessor map is still built on an assessor map.

Online providers differ in what their services actually include. Some hand back a drawing file and stop there; others check the sheet against a jurisdiction checklist before you attach it to permit applications. When comparing tools, look past the interface at what you can export: a scaled PDF at the sheet size your jurisdiction accepts, editable layers for revisions, and a legend you control. A cheap tool that forces a rebuild after the first correction cycle is not cheap.

When to Bring In Contractors, Engineers and Real Estate Professionals

Complicated zoning, stamped drawing requirements, structural or civil engineering, steep or flood-prone sites and subdivisions all justify professional site plans. Civil engineers handle grading, stormwater and utility design; landscape architects work through tree protection, planting and outdoor space; land use consultants translate urban planning rules into a layout that will survive review. Contractors price more accurately from a dimensioned plan than from a description, which keeps the owner, the trades and the reviewer on the same page about project details, and real estate professionals often want the same site plan drawing for disclosure, marketing and lot-value questions. Designers who prepare plans for clients regularly note that the drawing pays for itself the first time it catches an easement before excavation starts, and in many cases one avoided correction cycle covers the fee.

Review Your Site Plan Before Submitting It

• The entire parcel is shown, not a cropped portion
• North arrow, vicinity map, and both written and graphic scale are on the sheet
• All property boundaries are dimensioned
• Setbacks are drawn and labeled
• Existing, demolished and proposed work are clearly differentiated in a legend
• Easements and rights-of-way appear with their widths
• Utilities and drainage are addressed
• Coverage, impervious surface and other calculations are tabulated
• The site plan matches the floor plans, elevations, foundation plan and any civil plans (Bellevue warns that site and civil plans must not contradict each other)
• The complete PDF has been printed or viewed at submission size to confirm all the details and dimensions stay legible

Common Site Plan Mistakes That Cause Permit Corrections

• Drawing before reading the jurisdiction's checklist
• Treating a tax map or aerial image as a survey
• Measuring from fences or curbs instead of the legal property line
• Omitting easements and rights-of-way
• Forgetting eaves, decks, steps, retaining walls or small sheds
• Showing proposed work without dimensions
• No visual distinction between existing and proposed
• A written scale that breaks when the page is resized
• No grading or drainage information on a sloping site
• Using obsolete zoning or setback data
• Assuming an 811 locate marks privately owned lines
• Submitting a concept sketch where stamped or surveyed plans are required

Frequently Asked Questions

Can You Make Your Own Site Plan?

Often yes, for simple projects, as long as your jurisdiction accepts owner-prepared plans and your property boundaries are documented on a recorded survey or plat. Surveyed or stamped plans become necessary when property lines are uncertain, the project sits near a lot line, or the building official requires certification.

What Is an Example of a Site Plan?

A typical detached garage permit sheet: the parcel outline with dimensioned lot lines, dashed setback lines, the existing house with perpendicular distances to each boundary, the driveway and street with right-of-way width, the proposed footprint fully dimensioned, utility routes, plus a north arrow, vicinity map, scale and title block.

What Is an Easy Way to Draw a Site Plan?

Start from an existing survey or previously approved permit plans for the property. Trace it to scale on graph paper or into a site plan template, add your measured existing features, then draw the proposed work last as a separate, clearly labeled layer.

How Do You Draw a Site Plan for Beginners?

Pull the local checklist, gather your property documents, set up the sheet with a scale that fits the whole parcel, draw property boundaries and existing conditions, then add the proposed work with dimensions to every lot line and any required calculations.

Key Takeaway: A Site Plan Is a Compliance Document, Not an Illustration

Good site plans are not the ones with the most detail. They are the ones built on reliable data that answer the jurisdiction's questions and show clearly what exists, what will change, and whether the project complies with the rules affecting that property today. Pull your current checklist and your recorded survey before you draw anything, and bring in a surveyor, engineer or design-build contractor the moment your project touches a boundary, a slope, a hazard area or an existing structure.