Site Plan for Permit in Portland, OR | Fast Drawings

A residential site plan—also commonly called a plot plan—is an overhead drawing showing how a proposed project fits within the complete property.

It helps Portland Permitting & Development understand:

• Which property is being developed
• What structures and improvements already exist
• What work is proposed
• How large the project will be
• How far it will be from the property boundaries
• Whether trees, slopes, utilities or easements affect the location
• How the project changes paving, drainage or impervious area
• Whether the site plan agrees with the other permit drawings

A clear plan does not guarantee permit approval. It gives the reviewing authority measurable information about the property and proposed project.

What Is a Site Plan for a Portland Permit?

A site plan is a scaled drawing of the property as viewed from above.

It commonly identifies:

• Legal property boundaries
• Lot dimensions
• The existing house
• Garages and accessory structures
• Decks, porches and covered areas
• Driveways and parking
• Walkways and patios
• Proposed construction
• Distances to property lines
• Easements and utilities
• Trees and landscaping when required
• Existing and proposed ground elevations
• Stormwater facilities when required
• North arrow and drawing scale

The site plan is only one part of the permit package.

Depending on the project, Portland may also require:

• Existing and proposed floor plans
• Exterior elevations
• Building sections
• Foundation plans
• Structural details and calculations
• Energy-code information
• Tree plan
• Stormwater documentation
• Erosion-control plan
• Geotechnical engineering report
• Public Works plans
• Professionally signed or sealed documents

For a broader overview, read our complete Plot Plan for Permit guide .

Current Portland Site Plan Drawing Standards

Portland publishes specific presentation standards for residential permit drawings.

Portland does not accept a Google Maps or PortlandMaps image as a replacement for a properly prepared site plan for an addition application.

Online mapping can support property research, but the final permit drawing must contain clean linework, dimensions, labels and the required site information.

Official sources: City of Portland — Drawing a Site Plan and Building Permit Plans for Residential Projects .

Confirm the Correct Permitting Jurisdiction

A Portland postal address does not always mean the property is regulated by the City of Portland.

Properties in the wider Portland area may be reviewed by:

• City of Portland
• Another incorporated city
• Multnomah County
• Washington County
• Clackamas County
• A specialised district or public agency

Before preparing the drawings, confirm which authority will review the permit.

For properties within the City of Portland, Portland Permitting & Development administers building permits, zoning review and inspections.

PortlandMaps can help research:

• Property address and identification number
• Tax-lot information
• Base zoning
• Overlay zones
• Plan districts
• Previous permits
• Land-use decisions
• Flood hazards
• Steep slopes and mapped landslide areas
• Sewer and stormwater information
• Water service

PortlandMaps is a research resource. It does not independently establish a legal property boundary.

Official source: City of Portland — How to Get a Building Permit .

When Might a Portland Project Need a Site Plan?

A site plan is commonly required when a residential project adds a structure, enlarges a building footprint, changes vehicle access or alters the developed area of the property.

Projects can include:

• New house
• Home addition
• Accessory dwelling unit
• Attached or detached garage
• Carport
• Shed or accessory structure
• Deck or exterior stairs
• Porch or patio cover
• Swimming pool
• Retaining wall
• Driveway or parking expansion
• Substantial paving
• Grading or ground disturbance

Some projects that do not need a building permit may still require a zoning permit or must comply with zoning, tree, stormwater and property-development regulations.

Official source: City of Portland — Do You Need a Residential Permit? .

What a Portland Residential Site Plan Should Show

Property identification

Include:

• Complete property address
• Property identification or R number when requested
• Project title
• Short scope description
• Preparation or revision date

The property and project information should match the permit application and remaining drawings.

Complete property boundaries

Show the complete legal lot rather than only the area surrounding the proposed project.

The drawing should identify:

• Front property line
• Both side property lines
• Rear property line
• Street-side boundary on a corner lot
• Angled or curved lot-line segments
• Length of each boundary segment
• Adjoining streets
• Public alley where applicable

Do not automatically treat a fence, hedge, retaining wall, edge of paving or online parcel line as the legal property boundary.

Lot dimensions and area

Available boundary dimensions may come from:

• Licensed boundary survey
• Recorded subdivision plat
• Previous approved permit drawing
• Assessor or tax-lot information
• Measurements supplied by the property owner

PortlandMaps may help locate assessor information, but a licensed survey may be necessary when certified boundary accuracy is required.

Existing buildings and improvements

Show the existing features that affect the proposed project.

• Main house
• Attached garage
• Detached garage
• Carport
• Shed or accessory building
• Accessory dwelling unit
• Deck or porch
• Patio cover
• Swimming pool or spa
• Driveway and parking
• Walkways and patios
• Retaining walls
• Fences and gates when relevant

Omitting an existing structure can affect setback, building-separation, lot-coverage, tree or stormwater review.

Proposed construction

The proposed project should be clearly labelled and visually different from existing conditions.

Use:

• A clear “PROPOSED” label
• Different hatching
• A heavier outline
• A distinct line style
• An existing-and-proposed legend

Show the complete proposed footprint, including relevant:

• Exterior walls
• Supporting posts
• Deck platforms
• Stairs and landings
• Roof or eave projections
• Equipment pads
• New paving
• Structures proposed for removal

Project dimensions

Show the proposed project’s overall length and width.

Irregular projects should include enough dimensions to define the complete shape.

Site-plan dimensions should agree with:

• Floor plans
• Exterior elevations
• Foundation plans
• Structural drawings
• Manufacturer drawings
• Permit application

Distances to property lines

Show measurable distances from the proposed work to the relevant:

• Front property line
• Both side property lines
• Rear property line
• Street-side boundary
• Existing house
• Accessory structures
• Known easements

Measure roof or eave projections separately when they are relevant to the applicable zoning or building-code requirement.

Portland Setbacks and Zoning

There is no single Portland setback that applies to every residential project.

The required location can depend on:

• Base zone
• Overlay zone
• Plan district
• Structure type
• Building height
• Attached or detached construction
• Corner-lot conditions
• Garage-door orientation
• Fire-separation requirements
• Environmental regulations
• Historic-resource rules
• Previous land-use approvals

Portland measures setbacks horizontally rather than following the slope of the ground.

Identify the property’s zoning and plan-district information before finalising the proposed location.

Read Setbacks and Zoning: How to Find the Rules for Your Property and Property Setbacks Explained for Homeowners .

Official source: City of Portland — Common Zoning Questions .

Finished Grade, Elevations and Contours

Portland’s site-plan guidance includes finished-grade elevations at property corners and building corners.

Depending on the project, the plan may need to show:

• Reference elevation datum
• Existing grade at property corners
• Existing grade at building corners
• Proposed finished grade
• Contour lines
• Cut-and-fill areas
• Retaining walls
• Drainage direction

Contour lines may be needed where the ground elevation changes substantially across the property.

Accurate field elevations normally require information from a licensed surveyor, engineer or another qualified professional.

Steep Slopes and Geotechnical Engineering

A Portland property may need geotechnical engineering when:

• The project area has a slope greater than 20%
• The property is in or near a mapped landslide inventory area
• The proposed foundation is non-prescriptive
• The foundation will be placed on more than 12 inches of fill

A geotechnical report evaluates soil and slope conditions and may provide recommendations for foundations, retaining walls, drainage and site preparation.

A drafted site plan cannot replace a report prepared by an Oregon-licensed geotechnical engineer when one is required.

Official source: City of Portland — Residential Additions .

Driveways, Parking and Vehicle Access

Show the driveway and its relationship to:

• Street
• Property boundaries
• Garage or carport
• Parking spaces
• Public sidewalk
• Corner intersection
• Existing trees
• Utilities

Depending on the project, Portland may review:

• Driveway width at the property line
• Distance to side property lines
• Distance from a garage entrance to the street property line
• Driveway location on a corner lot
• Vehicle manoeuvring
• Changes within the public right-of-way

Clearly distinguish the private driveway from work in the public sidewalk, curb or street area.

Public right-of-way work may require a separate transportation or Public Works permit.

Easements, Utilities and On-Site Systems

Show recorded easements when they affect the proposed project.

These can include:

• Utility easements
• Drainage easements
• Access easements
• Shared-driveway easements
• Sewer easements
• Water easements

A project can satisfy the zoning setback and still conflict with an easement.

Depending on the property and project, the plan may also need to identify:

• Water line
• Sanitary sewer line
• Stormwater connection
• Septic tank
• Cesspool
• Drain field
• Utility meters
• Overhead or underground services

Portland’s addition guidance has additional requirements for projects involving existing septic systems, cesspools or new sewer connections.

Trees and Tree Plans

Portland’s tree regulations can affect project placement, excavation, construction access and material-storage areas.

When a tree plan is required, it must be drawn to scale and may need to show:

• Existing buildings and improvements
• Proposed structures
• Proposed impervious surfaces
• Grading and utility work
• Construction staging areas
• Trees completely or partly on the site measuring at least 6 inches in diameter
• Street trees measuring at least 3 inches in diameter
• Trees proposed for removal
• Trees proposed to remain
• Tree-protection measures
• Proposed replacement or new trees

For additions that expand the building footprint, Portland’s checklist instructs applicants with lots of at least 5,000 square feet to show the location, size and species of existing trees measuring 6 inches or more in diameter, together with existing street trees.

Tree-plan applicability and preservation obligations depend on the project, site and Portland Tree Code.

Official source: City of Portland — Tree Plan Requirements for Development Permits .

Stormwater and Impervious Area

Buildings, driveways, patios, walkways and other hard surfaces can increase the property’s impervious area.

Impervious surfaces reduce the amount of rainfall that can soak naturally into the soil.

Portland uses project-specific stormwater requirements.

For example:

• The residential-addition checklist requests stormwater-related documentation when an addition creates more than 500 square feet of new impervious area.
• The garage, shed and accessory-structure guidance calls for a stormwater plan on the site plan when the project adds more than 1,000 square feet of impervious area.

This is why homeowners should use the current checklist for their particular project rather than applying one threshold to every permit.

Required stormwater information may include:

• New roof and paving area
• Area draining to the stormwater facility
• Facility type and size
• Facility location
• Distance to property lines
• Distance to buildings
• Conveyance route
• Overflow or disposal method

A basic site plan does not replace a stormwater report, facility design or civil engineering when those services are required.

Erosion Control and Ground Disturbance

Excavation, grading and exposed soil can trigger erosion-control requirements.

Depending on the project and site, Portland may accept:

• A Simple Site Plan–Erosion Control Requirements form
• An erosion-control plan incorporated into the site plan
• A separate graphical erosion-control plan

A site may qualify as a simple site only when it satisfies Portland’s listed conditions concerning slope, disturbed area, waterways, environmental overlays, contamination and groundwater discharge.

Complex sites require more detailed information.

Erosion-control measures must be installed and maintained during construction even when a simplified form is accepted.

Portland Site Plan Requirements by Project Type

Home additions

A site plan for an addition should commonly show:

• Complete existing house
• Proposed addition footprint
• Addition dimensions
• Exterior walls and eaves
• Distances to property lines
• Total lot area
• Existing and proposed building areas
• Proposed paving
• Existing trees and street trees when required
• Major geographical or drainage features
• Septic or cesspool information when applicable
• Water, sewer and stormwater information when required

Portland requires the site plan to distinguish clearly between existing conditions and proposed work. A map photograph is not accepted as the addition site plan.

Official source: City of Portland — Residential Additions .

Garages, sheds and accessory structures

A building permit is required for a non-habitable accessory structure that is:

• More than 200 square feet, measured from the interior side of the exterior walls; or
• Taller than 15 feet, measured under Portland’s applicable height method.

A smaller non-habitable structure may not need a building permit, but a zoning permit or other review may still apply.

Habitable accessory structures require a building permit regardless of size.

A garage or shed site plan may need to show:

• Complete footprint
• Overall dimensions
• Height when relevant
• Distances to property lines
• Distance to the house
• Driveway access
• Roof projections
• Trees and utilities
• Building coverage
• Stormwater and erosion-control information

Official source: City of Portland — Garages, Sheds and Accessory Structures .

Accessory dwelling units

An ADU permit package may require:

• Complete property layout
• Primary dwelling
• Proposed attached or detached ADU
• Project dimensions
• Property-line distances
• Building separation
• Parking or access where applicable
• Water and sewer information
• Trees
• Stormwater and erosion control
• Geotechnical report for qualifying slope or landslide conditions

The site plan does not replace the ADU floor plans, elevations, sections, energy documents or structural drawings.

Decks and exterior stairs

Portland requires a building permit when any part of the deck walking surface is more than 30 inches above the ground, measured under the City’s current deck guidance.

A deck at or below that height may not need a building permit, but zoning requirements still apply.

A deck site plan may identify:

• Deck footprint
• Deck height
• Connection to the house
• Stairs and landings
• Supporting posts
• Distances to property lines
• Nearby structures
• Trees and easements

Separate structural plans explain the footings, posts, beams, joists, stairs, guards and handrails.

Official source: City of Portland — Residential Deck Permit Research .

Retaining walls

A Portland building permit is required when a retaining wall:

• Is more than four feet high, measured from the bottom of the footing to the top of the wall; or
• Supports a surcharge such as a building, driveway or other additional load.

A wall that does not require a building permit may still need zoning review.

A retaining-wall site plan may show:

• Wall alignment
• Wall length
• Wall height
• Property boundaries
• Nearby buildings and driveways
• Existing and proposed grade
• Drainage
• Slopes
• Trees and utilities

Structural or geotechnical engineering may be required depending on the wall and site conditions.

Official source: City of Portland — Retaining Wall Permits .

Driveways and public right-of-way work

A driveway site plan should distinguish:

• Private property
• Public sidewalk
• Driveway apron
• Curb
• Street
• Existing and proposed driveway
• Parking area
• Garage entrance
• Nearby trees and utilities

Construction within the public right-of-way follows a different review process from work entirely on private property.

Drafted Site Plan vs Survey vs Engineering Plan

A licensed land surveyor may be necessary when:

• No reliable survey or plat is available
• Property corners cannot be located
• The proposed work is close to a boundary
• The lot is irregular
• Available records conflict
• There is a boundary dispute
• Certified elevations are required
• The City requests current survey information

A drafted site plan does not replace:

• Boundary survey
• Structural engineering
• Geotechnical engineering
• Grading or drainage design
• Stormwater engineering
• Architectural plans
• Professional signatures or seals

Current Portland Electronic Permit Process

Portland uses Development Hub PDX—commonly called DevHub—for permit applications.

The current process generally works as follows:

A permit technician may return an application during prescreen when drawings or supporting information do not meet the minimum submission requirements.

Official sources: Submit a Permit Application Through DevHub and ProjectDox Online Plan Review .

What to Send With Your Portland Site Plan Order

Complete source information helps reduce uncertainty while the drawing is being prepared.

How Our Portland Site Plan Service Works

1. Place your order. Choose the site-plan option matching the requested level of detail.
2. Provide the property address. Confirm that the City of Portland is the reviewing authority.
3. Upload your documents. Send any survey, plat, previous drawing or permit comments.
4. Describe the project. Provide the proposed dimensions, height and scope.
5. Mark the proposed location. Send a sketch, photographs or contractor drawings showing the intended placement.
6. Review the completed drawing. Check the property layout, project location, dimensions and labels.
7. Confirm the complete permit package. Obtain any separate architectural, structural, tree, stormwater, geotechnical or surveying documents required by Portland.

The accuracy and usefulness of the completed drawing depend on the accuracy of the surveys, records, measurements, photographs and project information supplied.

Common Portland Site Plan Problems

• The wrong permitting jurisdiction is assumed
• Only the immediate project area is shown
• The complete lot is missing
• Property boundaries are estimated from a fence
• Lot dimensions are missing
• The existing house is incomplete
• Garages or accessory buildings are omitted
• The proposed work is not clearly distinguished
• Project dimensions are missing
• Exterior-wall or eave setbacks are unclear
• The site plan conflicts with the floor plans
• A Google Maps or PortlandMaps image is submitted as the plan
• The north arrow or scale is missing
• The drawing is not black and white
• Text and dimensions are difficult to read
• Easements are ignored
• Trees near construction are omitted
• Grade and slope conditions are not addressed
• Stormwater requirements are overlooked
• Erosion-control information is missing
• A drafted plan is submitted where a survey or engineering is required

A complete drawing cannot eliminate every review comment, but it can reduce corrections caused by missing or inconsistent site information.

Read Why Site Plans Get Rejected for Permits .

Portland Residential Site Plan Checklist

Related Site Plan Guides

Frequently Asked Questions

Does every Portland residential permit require a site plan?

No. The required drawings depend on the project. Work that adds a structure, enlarges a building footprint, changes vehicle access, creates substantial paving or disturbs the site is more likely to require one.

What scale does Portland require for a residential site plan?

Portland requires a site-plan scale of 1 inch equals 10 feet or larger. The scale used must be clearly stated on the drawing.

What sheet size should I use?

The site plan must be prepared on an 11-by-17-inch or larger sheet. Portland instructs applicants to use the same sheet size throughout the permit drawing set.

Can I submit a PortlandMaps or Google Maps image?

Not as a replacement for the required addition site plan. Portland requires a scaled, black-and-white drawing showing the complete lot, dimensions and clearly identified existing and proposed work.

Do I need a permit for a shed or detached garage?

A building permit is required when a non-habitable accessory structure exceeds 200 square feet or is taller than 15 feet. Smaller structures may still require zoning review and must comply with applicable placement, coverage, tree and other rules.

When does a deck require a building permit?

A building permit is required when any part of the walking surface is more than 30 inches above the ground under Portland’s current deck-measurement guidance. Zoning rules apply even when a building permit is not required.

When does a retaining wall need a permit?

A building permit is required when the retaining wall is more than four feet high from the bottom of the footing to the top of the wall or supports an additional surcharge.

Do I need a tree plan?

Tree-plan requirements depend on the development activity, site and trees present. When a tree plan applies, it must identify existing trees, proposed work, construction areas and tree-protection or removal information required by Portland.

Do I need stormwater information?

Possibly. Portland uses different stormwater triggers for different project types. Use the current project-specific checklist rather than assuming one impervious-area threshold applies to every permit.

When is a geotechnical report required?

It may be required for projects on slopes greater than 20%, properties in or near mapped landslide areas, non-prescriptive foundations or foundations placed on more than 12 inches of fill.

Can a drafted site plan establish my legal property lines?

No. A drafted plan uses available boundary information but does not independently establish or certify legal property boundaries. Hire a licensed land surveyor when boundary certification is required.

Are USA Site Plans drawings signed or sealed?

No. USA Site Plans provides drafting services. Licensed surveying, architecture, structural engineering, geotechnical engineering, civil engineering and professional seals must be obtained separately when required.

Will a Portland site plan guarantee permit approval?

No. Portland Permitting & Development and any other participating agencies control approval and may request revisions, a survey, tree information, engineering or other supporting documents.

Official Portland Resources

• City of Portland — Drawing a Site Plan
• Building Permit Plans for Residential Projects
• How to Get a Building Permit
• Do You Need a Residential Permit?
• Residential Additions
• Garages, Sheds and Accessory Structures
• Residential Deck Permit Research
• Retaining Wall Permits
• Tree Plan Requirements
• Common Zoning Questions
• Submit a Permit Application Through DevHub
• ProjectDox Online Plan Review

Disclaimer: This article provides general educational information and is not legal, surveying, engineering, architectural, arboricultural, zoning or permitting advice. Portland requirements vary according to the property, jurisdiction, zoning, project type, trees, slopes, easements, stormwater conditions and current regulations. USA Site Plans is an independent drafting service and is not affiliated with the City of Portland or Portland Permitting & Development. A drafted site plan does not establish legal property boundaries or replace a licensed survey, engineering, architecture or another professionally certified document when required. Confirm current requirements with the authority reviewing your application.