Homeowners often use the terms plot plan and site plan interchangeably. Seattle Department of Construction and Inspections materials generally use the term site plan.

The purpose is the same: show the complete property from above so reviewers can determine where the project will be located and how it relates to the boundaries, buildings, driveways, alleys, trees and other site conditions.

What Is a Plot Plan?

A plot plan is a scaled or dimensioned overhead drawing showing how a property is arranged.

A residential plot plan commonly identifies:

• Legal property boundaries
• Lot dimensions
• The existing house
• Garages, sheds and accessory structures
• Decks, patios and porches
• Driveways, alleys and parking areas
• Proposed construction
• Distances to property lines
• Known easements
• Streets and sidewalks
• A north arrow
• A drawing scale

The drawing does not replace floor plans, structural drawings or elevations. It serves a different purpose by showing where the project sits on the property.

Read our complete plot plan for permit guide for a broader explanation.

Does Seattle Call It a Plot Plan or Site Plan?

Seattle SDCI generally refers to the document as a site plan.

Seattle’s permit-process page instructs applicants to include a site plan meeting the requirements of Tip 103. Depending on the project, the preliminary application may need either:

• A preliminary site plan
• A simple site plan
• A more detailed permit site plan
• An environmentally critical area site plan
• A site plan supported by a topographic survey

Therefore, a homeowner searching for a “Seattle plot plan” is normally looking for the same general property-layout drawing Seattle calls a site plan.

Official source: Seattle SDCI — How to Get a Permit .

When Do You Need a Plot Plan in Seattle?

You commonly need a site plan when the proposed work changes the exterior layout, footprint, access, developed area or ground conditions of the property.

Examples include:

• Building a home addition
• Constructing a detached garage
• Adding a backyard cottage or accessory dwelling unit
• Building a deck above the permit-exemption height
• Installing a shed that requires a permit
• Constructing a tall or regulated fence
• Building a retaining wall requiring approval
• Adding or replacing substantial paving
• Widening or relocating a driveway
• Changing the building footprint
• Completing exterior work on an environmentally critical area site
• Grading or disturbing a substantial area of land

A Subject-to-Field-Inspection application also requires a site plan and complete legal description. SDCI states that the plans should be drawn to scale, easy to read and clearly show existing conditions and proposed alterations.

Official source: Seattle SDCI — Subject-to-Field-Inspection Permits .

When Might You Not Need a Permit or Plot Plan?

Seattle lists several types of smaller work that generally do not require a construction permit when all exemption conditions are met.

Permit-exempt work can include:

• A one-story detached accessory building with a projected roof area under 120 square feet and a slab-on-ground foundation
• Certain retaining walls and rockeries no more than 4 feet high, measured from the bottom of the footing
• Fences under 8 feet high without concrete or masonry elements higher than 6 feet
• Open-framed landscape structures no larger than 120 square feet
• Patios and concrete slabs located on grade
• Platforms, walks and driveways less than 18 inches above grade and not located over a basement or another building story

These exemptions are not universal permission to build anywhere on the property.

SDCI states that even work not requiring a permit must comply with applicable code requirements and development standards. Additional rules may apply when the property contains an environmentally critical area.

Official source: Seattle SDCI — Do You Need a Permit? .

What Must a Seattle Plot Plan Show?

The exact contents depend on the permit type and site conditions. A Seattle residential site plan commonly includes the following items.

Property identification

• Complete property address
• Legal description
• King County Assessor parcel number when required
• Project title and description
• Preparation or revision date

Property boundaries

• Front property line
• Both side property lines
• Rear property line
• Angled or curved boundaries
• Available boundary dimensions
• Street and alley relationships

Do not automatically use a fence, hedge, retaining wall or edge of paving as the legal property boundary.

Existing structures

• Main house
• Attached or detached garage
• Sheds and accessory structures
• Decks, patios and porches
• Swimming pools
• Retaining walls and rockeries
• Driveways and parking areas
• Walkways
• Fences and gates when relevant

Proposed work

• Complete proposed footprint
• Overall project dimensions
• Connection to the existing house
• Stairs and landings
• Roof overhangs
• Supporting posts
• New paving
• Structures proposed for removal

Setbacks and building separation

Show measurable distances from the proposed work to:

• Front property line
• Both side property lines
• Rear property line
• The existing house
• Other structures
• Known easements
• The adjoining street or alley when relevant

Access and paved areas

• Driveway location
• Parking areas
• Alley access
• Street connection
• Sidewalks
• Walkways
• Existing and proposed paving

Scale and orientation

• North arrow
• Written drawing scale
• Graphic scale bar where helpful
• Street names
• Existing and proposed legend

Additional information when required

• Trees and tree-protection areas
• Contour lines
• Existing and proposed ground elevations
• Environmentally critical area boundaries
• Drainage and stormwater features
• Utilities
• Lot-coverage calculations
• Impervious-area calculations
• Public right-of-way features

Read our complete site plan checklist for more detail.

Seattle Plot Plan Requirements by Project

Deck Plot Plans in Seattle

Seattle requires a construction permit when a deck is:

• More than 18 inches above the ground
• A roof deck
• Located in an environmentally critical area

Most qualifying residential decks use the Subject-to-Field-Inspection permit process, although larger or more complicated decks may require an addition or alteration permit.

A deck plot plan should show the deck footprint, height, stairs, landings, connection to the house and distance from property lines.

Official source: Seattle SDCI — Decks .

Garage Plot Plans in Seattle

Most new or remodelled garages require a Subject-to-Field-Inspection permit when the garage:

• Is 750 square feet or less
• Is one story without a roof deck
• Has beams spanning no more than 14 feet
• Is not located on a property containing an environmentally critical area

A garage plot plan commonly shows the garage footprint, setbacks, separation from the house, driveway or alley access and additional paved areas.

Official source: Seattle SDCI — Garages .

Shed Plot Plans in Seattle

A one-story shed with a projected roof area under 120 square feet and only a slab-on-ground foundation may be exempt from a construction permit.

The shed must still comply with placement, height, lot-coverage and environmentally critical area rules.

A larger or nonqualifying shed generally requires a permit, and a plot plan may need to show:

• Shed dimensions
• Height
• Rear and side setbacks
• Distance to the house
• Known easements
• Access

Read our related guide: Plot Plan for a Shed Permit in Seattle .

Fence Plot Plans in Seattle

Seattle generally does not require a construction permit for a fence under 8 feet high when it contains no concrete or masonry elements higher than 6 feet.

A permit is required when the fence is located in a flood-prone area. Taller fences requiring approval need scaled plans, including a site plan and construction details.

Even where no permit is required, fence placement may still be affected by visibility, retaining-wall, property-boundary and private restriction issues.

Official source: Seattle SDCI — Fences .

Retaining Wall Plot Plans

A retaining wall or rockery may be exempt from a construction permit when:

• It is no more than 4 feet high measured from the bottom of the footing
• The property does not contain an environmentally critical area
• The work will not damage neighbouring property or structures

When a permit is required, the site plan may need to show the complete wall, height, footing relationship, slopes, boundaries, nearby structures and grading.

Official source: Seattle SDCI — Retaining Walls and Rockeries .

Driveways, Paving and Grading

A driveway or paving project may require a site plan showing the existing and proposed hard surfaces, street connection, sidewalk, parking, property lines and drainage direction.

Seattle requires a grading permit when a project adds or replaces a combined 750 square feet or more of hard surface, including pavement.

Additional review may apply when the project changes the grade, disturbs a steep slope or affects an environmentally critical area.

Official source: Seattle SDCI — Grading Permit .

Environmentally Critical Area Properties

Some Seattle sites contain environmentally critical areas such as:

• Steep slopes
• Known or potential landslide areas
• Liquefaction-prone areas
• Wetlands
• Flood-prone areas
• Shoreline areas
• Wildlife habitat areas

Exterior work on an ECA property may require additional documents beyond a basic drafted site plan.

For example, SDCI may require:

• A topographic survey
• A geotechnical report
• An ECA site plan
• Drainage information
• A Pre-Application Site Visit
• An exemption or waiver application

SDCI states that a topographic survey is required for certain exterior work or foundation alterations on properties containing specified steep-slope or known-slide areas.

A basic residential drafting service does not replace those licensed professional documents.

Do You Need a Survey Before Getting a Seattle Plot Plan?

Not every project requires a new survey.

A drafted plot plan may sometimes use:

• An existing boundary survey
• A recorded plat
• A previous approved site plan
• Property records
• Aerial imagery
• Customer-supplied measurements

A licensed survey may be required when:

• Legal boundaries are uncertain
• The proposed work is close to a property line
• Accurate elevations or contours are needed
• The property contains certain environmentally critical areas
• Existing documents conflict
• There is a boundary dispute
• SDCI specifically requests certified information

Read Seattle Plot Plan vs Survey for a detailed comparison.

How to Find Existing Property Information

Before preparing a plot plan, check whether useful property documents already exist.

Possible sources include:

• Your closing or title documents
• An existing boundary survey
• A recorded subdivision plat
• Previous approved permit plans
• King County Assessor information
• Seattle permit records
• Builder or contractor drawings

An old plan can be a helpful starting point, but it should be checked against current property conditions and the proposed project.

Seattle provides information about obtaining historical permit documents through its Research a Project, Permit or Property page.

Common Plot Plan Problems

A site plan may be returned for corrections when the reviewing authority cannot identify or verify the project information.

Common problems include:

• The complete property is not shown
• Lot dimensions are missing
• The existing house is incomplete
• Accessory structures are omitted
• Proposed work is not clearly labelled
• Project dimensions are missing
• Setback measurements are missing
• Distances between structures are unclear
• The street or alley is not shown
• No drawing scale is provided
• No north arrow is included
• Trees are omitted when protection requirements apply
• Known easements are ignored
• Slope or ECA conditions are omitted
• The plot plan conflicts with other submitted drawings

A clear drawing does not guarantee approval, but it can reduce correction requests caused by incomplete or confusing site information.

How Our Seattle Plot Plan Service Works

1. Place your order. Select the site-plan option matching the required level of detail.
2. Provide the property address. Available mapping and property information can be reviewed.
3. Upload your documents. Send any survey, plat, old plan or permit comments you have.
4. Describe the project. Provide its length, width and other relevant dimensions.
5. Mark the proposed location. Send a sketch, photograph or marked aerial image.
6. Review the drawing. Confirm the project location, dimensions and labels.
7. Request reasonable edits. Site-plan revisions can be made when SDCI requests drawing corrections.

The accuracy of a remotely prepared plot plan depends on the quality and accuracy of the property records, surveys, photographs, measurements and project information supplied.

Frequently Asked Questions

Do I need a plot plan for a Seattle building permit?

Many Seattle construction and land-use applications require a site plan meeting SDCI Tip 103. The exact plan type and detail depend on the permit and property conditions.

Is a plot plan the same as a site plan in Seattle?

The terms are often used interchangeably by homeowners. Seattle SDCI generally uses the term site plan in its application guidance.

Do I need a plot plan for a small shed?

A small one-story shed under 120 square feet with a slab-on-ground foundation may be exempt from a construction permit. It must still satisfy applicable zoning, placement, height and ECA requirements.

Do I need a plot plan for a deck?

A site plan is commonly required when the deck needs a permit. Seattle requires a permit for decks more than 18 inches above the ground, roof decks and decks located in environmentally critical areas.

Do I need a plot plan for a fence?

A permit is generally not required for a fence under 8 feet high without concrete or masonry elements over 6 feet. Flood-prone locations and taller fences may require a permit and scaled plans.

Can I draw my own Seattle plot plan?

Seattle may accept owner-prepared plans when they satisfy Tip 103 and the applicable permit checklist. Plans should be drawn to scale, readable and complete.

Can I use Google Maps or aerial imagery?

Aerial imagery can help identify visible structures and general layout, but it should not automatically be treated as proof of legal property boundaries.

Do I need a licensed survey?

Not for every project. A licensed survey may be needed where boundaries are uncertain, certified elevations are required, the project is close to a lot line or the site contains certain environmentally critical areas.

Are USA Site Plans drawings stamped?

No. USA Site Plans provides residential drafting services. Licensed surveys, architectural seals, engineering, drainage design, geotechnical reports and stamped ECA plans must be obtained separately when required.

Will a plot plan guarantee permit approval?

No. Seattle SDCI controls permit approval and may request corrections, certified survey information, engineering or other supporting documents.

Official Seattle Sources

• Seattle SDCI Tip 103 — Site Plan Guidelines and Requirements
• Seattle SDCI — How to Get a Permit
• Seattle SDCI — Do You Need a Permit?
• Seattle SDCI — Subject-to-Field-Inspection Permit
• Seattle SDCI — Decks
• Seattle SDCI — Garages
• Seattle SDCI — Fences
• Seattle SDCI — Retaining Walls and Rockeries
• Seattle SDCI — Grading Permit

Disclaimer: This article provides general educational information and is not legal, surveying, engineering, architectural, geotechnical, zoning or permitting advice. Seattle requirements vary according to the property, project, zoning, environmentally critical areas and current regulations. A drafted site plan does not establish legal property boundaries or replace licensed professional documentation when required. Confirm current requirements with Seattle SDCI before submitting an application or beginning construction.