Do you need a site plan for a deck permit? In many cities and counties, the answer is yes. When a deck requires a building permit, zoning permit or residential-lot review, the application will commonly include a scaled site plan showing where the deck will sit on the property.

The plan helps permit reviewers check the deck’s size, location, height, boundary setbacks, relationship to the house, easements and other site conditions. It is normally submitted alongside structural deck drawings showing the footings, posts, beams, joists, stairs, guards and attachment details.

Permit rules are local. A small, low, freestanding deck may be exempt in one jurisdiction but require a building or zoning permit in another. Always confirm the rules with the city, county or other authority responsible for your property before construction begins. [1][2][3][4][5]

When Is a Site Plan Required for a Deck?

A site plan is commonly required when the deck application must be reviewed for building-code or zoning compliance.

You are more likely to need one when the proposed deck:

• Is attached to the house
• Is elevated above the surrounding ground
• Provides access to an exterior door
• Includes stairs, landings or guards
• Is close to a property line
• Extends into a required setback
• Is being built in a floodplain or environmentally sensitive area
• Is located over or near an easement
• Includes a roof, pergola, screened enclosure or covered area
• Supports a hot tub or another concentrated load
• Changes the size or footprint of an existing deck
• Requires zoning, tree, drainage or stormwater review

Minneapolis, for example, requires deck permit applicants to provide construction plans consisting of a site plan, framing plan and cross section. Its site plan guidance calls for property lines and dimensions locating the house, garage and proposed deck. [1]

Portland also distinguishes between the site plan and the structural drawings. Its deck guidance says the site plan shows where the deck will go on the property, while structural plans explain how the deck will be built and an elevation drawing shows its height above grade. [6]

Does Every Deck Require a Permit?

No single rule applies throughout the United States. Permit exemptions depend on the locally adopted codes, zoning rules and site conditions.

Official requirements illustrate how much the thresholds can vary:

• Austin: A deck may be exempt from a building permit when it is no larger than 200 square feet, no more than 30 inches above grade, detached from the dwelling, does not provide egress and is outside a flood-hazard area. Exempt work must still comply with applicable codes and ordinances. [2]
• Seattle: A construction permit is required for decks more than 18 inches above the ground, roof decks and decks in certain environmentally critical areas. [3]
• Denver: An uncovered deck more than 12 inches above the ground requires a zoning permit, while a deck 30 inches or more above the ground also requires a building permit. Covered structures require both. [4]
• Portland: A building permit is required for an uncovered deck more than 30 inches above grade. A lower deck may be exempt from the building permit only when it also satisfies other location conditions, while zoning requirements still apply. [5]
• Montgomery County, Maryland: A building permit is required for all decks regardless of their height above grade. [8]

This is why advice from a contractor, neighbour or online discussion may not match the rules applying to your address.

What Is a Deck Permit Site Plan?

A deck permit site plan is a scaled, overhead drawing showing the property and the proposed deck.

It helps the reviewer answer practical questions such as:

• Where will the deck be built?
• How large will it be?
• How close will it be to the property lines?
• Is it attached to the house or freestanding?
• Will stairs extend closer to a boundary?
• Does the deck cross an easement?
• Will it affect a driveway, walkway or other structure?
• How high will it sit above the ground?
• Does the project affect trees, drainage or a flood-hazard area?

Montgomery County’s published site-plan requirements for decks call for items including the drawing scale, property lines, streets, existing and proposed structures, site features, structure height and area, setbacks, lot coverage and easements. [7]

What Should a Site Plan for a Deck Permit Show?

Exact submittal requirements vary, but the following details are commonly useful for a residential deck application.

Property Boundaries

Show the complete legal outline of the lot, including:

• Front property line
• Side property lines
• Rear property line
• Length of each boundary
• Lot width and depth
• Irregular or angled boundaries

The property lines are the reference points used to measure the deck’s setbacks.

Do not automatically treat a fence, hedge or row of trees as the legal boundary. Minneapolis specifically warns that a fence may indicate the approximate boundary but is not necessarily the property line. When relevant property corners cannot be located, a licensed surveyor may be needed. [1]

Street, Alley and Address

Show the street name and the side of the property facing the road.

Where applicable, also show:

• Public alley
• Corner-lot frontage
• Side street
• Public right-of-way
• Property address

Montgomery County asks applicants to show the address and street or alley location, while Portland requires public right-of-way information on its residential site plans. [6][8]

Existing House

Draw and label the existing dwelling.

Show:

• House footprint
• External walls
• Roof outline where relevant
• Exterior door serving the deck
• Wall where the deck will be attached
• Nearby windows

The relationship between the house and deck should be clear. An attached deck may require ledger and connection details that are not needed for a fully freestanding design.

Other Existing Structures

Show nearby structures and improvements that could affect the project, including:

• Garage or carport
• Shed
• Patio or porch
• Existing deck
• Swimming pool
• Retaining walls
• Driveway
• Walkways and steps
• Mechanical equipment
• Septic system or private well where applicable

Official site-plan guidance from Portland and Montgomery County includes existing buildings, patios, driveways, walkways, steps and other relevant site features. [6][7]

Proposed Deck Footprint

Clearly label the new work as:

Proposed Deck

Use a bold outline, hatching or another clear line style so the deck can be distinguished from the existing house and other structures.

Where an old deck will be removed, identify:

• Existing deck to be demolished
• Existing deck footprint
• New proposed deck footprint
• Any part of the old deck that will remain

Deck Dimensions and Area

Show the overall length and width of the proposed deck.

Also show dimensions for:

• Changes in deck shape
• Angled or curved portions
• Landings
• Built-in projections
• Stair width
• Any covered portion

Include the deck area in square feet where required. The total area can affect permit exemptions, building coverage and zoning review.

Front, Side and Rear Setbacks

Show the shortest measured distance from the deck to each nearby property line.

Depending on the design, separately dimension the:

• Main deck platform
• Stairs
• Landings
• Roof or canopy
• Built-in benches or privacy screens
• Other projections

Deck setback rules depend on the local zoning district, deck height and design features. Fairfax County, for example, states that decks are regulated by setback requirements, although certain decks may be allowed to extend into a setback depending on their height and features. [10]

Distance to Other Buildings

Show the distance between the proposed deck and:

• Detached garage
• Shed
• Accessory dwelling unit
• Neighbouring structure where relevant
• Pool or pool barrier
• Retaining wall

Portland’s site-plan instructions call for distances between buildings and between buildings and property lines. [6]

Deck Height Above Grade

Deck height is important because it can affect:

• Whether a building permit is required
• Whether guards are required
• Which setbacks apply
• How stairs are designed
• Whether an elevation drawing is needed

Show the distance from the surrounding ground to the top of the deck walking surface.

On sloping land, show the height at more than one point. A deck may be close to grade beside the house but substantially elevated at the outer edge.

Montgomery County requires the site plan to include the height from grade to the top of the deck, while Portland requires an elevation drawing showing the actual or proposed grade and deck height. [6][8]

Stairs and Landings

Show the location and direction of the deck stairs.

Include:

• Stair width
• Bottom landing
• Intermediate landing where applicable
• Direction of travel
• Distance from the landing or stair to the property line
• Connection to a walkway, yard or driveway

Stairs are easy to overlook when measuring setbacks. The deck platform may comply while the bottom landing quietly wanders into the required yard like it owns the place.

Deck Attachment

Identify whether the deck is:

• Attached to the house
• Freestanding beside the house
• Completely detached elsewhere on the lot

An attached deck generally needs structural details showing how the ledger or other connection will be fastened and protected from water intrusion.

A freestanding deck still needs footing, post, beam and lateral-stability details, but it does not depend on the house wall for support.

Footing and Post Locations

The site plan may show the general deck footprint, while the framing or foundation plan normally shows the exact footing and post layout.

Structural drawings commonly identify:

• Footing locations
• Footing size and depth
• Post size and spacing
• Beam location and size
• Joist direction, size and spacing
• Cantilevers
• Stair supports

Minneapolis requires a framing plan showing the overall deck size, footings, posts, beams, joists, decking and stairs. Montgomery County likewise requires complete structural details in the construction plans. [1][8]

Easements

Show and label all known easements affecting the property.

Common examples include:

• Utility easement
• Drainage easement
• Sewer easement
• Access easement
• Stormwater easement

Show the width and purpose of the easement and its relationship to the deck, stairs and footings.

Portland tells deck applicants to mark the easement and label its purpose. Montgomery County warns that construction must not encroach into the ground or air space of certain county easements. [6][8]

Utilities, Septic Systems and Wells

Where applicable, identify nearby:

• Sewer lines
• Water services
• Electrical or communication lines
• Septic tanks
• Drain fields
• Private wells

Montgomery County directs owners of lots served by septic systems or private wells to confirm the necessary construction clearances. [8]

Before digging footings, verify underground utility locations through the appropriate local utility-location service.

Trees and Landscaping

Show trees where construction, excavation or access may affect them.

The plan may need to identify:

• Tree-trunk location
• Tree size and species
• Trees to remain
• Trees proposed for removal
• Tree-protection fencing
• Root-protection areas

Portland requires additional tree information for certain deck projects. Charlotte’s individual residential-lot review can also include urban-forestry review, depending on the project and property conditions. [6][9]

Drainage, Grading and Slopes

A deck usually has an open walking surface, but its footings, stairs, landings and grading can still affect drainage.

Show relevant:

• Direction of surface-water flow
• Existing and proposed ground levels
• Slopes beneath and around the deck
• Retaining walls
• Drainage easements
• Areas of excavation or fill

For uneven properties, Portland requires grade elevations and may require contours and retaining-wall levels. Charlotte reviews drainage, stormwater infrastructure and floodplain issues for applicable residential projects. [6][9]

Flood-Hazard and Environmental Areas

Special requirements may apply when the property is in a:

• Floodplain
• Landslide-prone area
• Wetland or river overlay
• Environmentally critical area
• Historic district

Seattle requires permits for decks in certain environmentally critical areas, while Portland may require flood-hazard boundaries, elevations and protection information on the site plan. [3][6]

North Arrow and Drawing Scale

Include a north arrow and prepare the drawing at a consistent scale.

Possible site-plan scales include:

• 1 inch = 10 feet
• 1 inch = 20 feet
• 1/8 inch = 1 foot
• 1/4 inch = 1 foot for a small detailed area

Use a scale that allows the deck, structures, setbacks and property lines to remain readable.

Portland’s deck instructions require a scaled plan and list the north arrow as a site-plan item. [6]

Site Plan vs Structural Deck Plan

A site plan does not replace the deck’s structural drawings.

The site plan shows:

• Property layout
• Deck location
• Property lines
• Setbacks
• Existing buildings
• Easements
• Relevant site conditions

The structural or framing plan shows:

• Joists
• Beams
• Posts
• Footings
• Ledger attachment
• Connections and fasteners
• Stairs
• Guards and handrails

The elevation or cross section shows:

• Deck height above grade
• Footing depth
• Post and beam arrangement
• Joist depth
• Stairs and landings
• Guards and handrails
• Connection to the house

Minneapolis, Portland and Montgomery County all distinguish between site information and structural deck information in their published submittal guidance. [1][6][8]

Do You Need a Survey for a Deck Permit?

Not every deck application requires a new boundary survey. An existing house-location survey, property survey or recorded plat may be usable as the base for the proposed site plan.

A new or updated survey may be needed when:

• Property corners cannot be located
• The deck is close to a boundary
• The fence location is unreliable
• The lot has an unusual shape
• An easement location is uncertain
• The permitting authority specifically requests a survey
• The property is in a flood-hazard area

Minneapolis advises applicants to contact a licensed surveyor when the relevant property corners cannot be located. Portland also notes that a survey by a licensed surveyor or engineer may be required for certain flood-hazard sites. [1][6]

A drafted permit site plan is not a boundary survey and should not be represented as one.

Replacing an Existing Deck

Replacing an existing deck does not automatically mean the project is exempt.

A permit may still be required when:

• The framing is being replaced
• The deck is being rebuilt in the same location
• The size or shape is changing
• The stairs are moving
• The deck height is changing
• The attachment to the house is being altered
• Footings, posts or guards are being replaced

Minneapolis states that deck projects require a permit even when an old deck is being demolished and reconstructed at the same size, subject to its limited exception for certain low, remote decks. [1]

Show the old and new deck footprints clearly if the replacement design changes.

Covered Decks, Roofs and Pergolas

Adding a roof, pergola or screened enclosure can change the permit and zoning requirements.

A covered structure may:

• Count toward building or lot coverage
• Need larger footings
• Create additional wind and snow loads
• Need different setbacks
• Require structural engineering
• Be treated more like an addition to the house

Denver requires zoning and building permits for covered patios, porches, pergolas and carports. Portland explains that covered decks count as part of the building and must satisfy applicable setback requirements. [4][6]

Clearly show the roof outline and supporting posts when any portion of the deck will be covered.

Decks Supporting Hot Tubs

A deck supporting a hot tub, spa, outdoor kitchen, masonry fireplace or another heavy concentrated load may require engineered structural information.

Montgomery County requires sealed design-professional plans for a deck supporting a hot tub, including manufacturer information showing the structural loading requirements. [8]

The site plan should identify the hot-tub location, while the structural plans should demonstrate that the deck and foundations can safely support it.

HOA and Private Restrictions

A city or county permit does not necessarily satisfy homeowners association rules or private deed restrictions.

Before finalising the design, check for:

• Architectural-review approval
• Material or colour restrictions
• Additional setback requirements
• Privacy-screen rules
• Limits on deck size or height

Montgomery County notes that private covenants may regulate deck construction beyond county requirements and directs owners to their HOA or civic association for those restrictions. [8]

Common Deck Site Plan Mistakes

Applications can be delayed when the site plan is incomplete, unclear or inconsistent with the construction drawings.

Common mistakes include:

• Property lines are missing
• The fence is incorrectly used as the property boundary
• The deck is not clearly marked as proposed work
• Deck length or width is missing
• Setbacks are not shown
• Stairs and landings are omitted
• The deck height above grade is missing
• The existing house footprint is inaccurate
• A garage, shed, pool or retaining wall is omitted
• Easements are not shown
• The site plan and framing plan show different deck dimensions
• The plan is not drawn to scale
• The street and north arrow are missing
• Existing and proposed decks are not distinguished
• A roof, hot tub or other additional load is not identified
• Drainage, slope or flood conditions are ignored

What Information Is Needed to Prepare the Site Plan?

Collect as much of the following information as possible:

• Property address
• Deck length and width
• Deck height above grade
• Attached or freestanding design
• Stair and landing location
• Preferred deck location
• Distances to nearby property lines
• Photos of the house and backyard
• Rough sketch with measurements
• Existing survey or house-location plan
• Recorded plat if available
• Deck framing or contractor drawings
• Known easements
• Nearby structures
• Site slope or retaining-wall information
• Permit reviewer comments

Deck Permit Site Plan Checklist

Does a Site Plan Guarantee Permit Approval?

No. A clear site plan helps reviewers understand the deck’s proposed location, but permit approval also depends on the structural design, zoning rules, adopted building code and property conditions.

The application may also require:

• Framing or foundation plan
• Cross sections
• Elevation drawings
• Footing details
• Stair and guard details
• Ledger-attachment details
• Structural calculations
• Boundary survey
• Floodplain or environmental review
• Tree or stormwater review
• Electrical permit
• HOA approval

Need a Site Plan for a Deck Permit?

Site Plan Pros prepares clear residential site plans for homeowners, contractors and permit applications.

Your deck site plan can show:

• Property boundaries
• Existing house and structures
• Proposed deck location
• Deck dimensions
• Boundary setbacks
• Stairs and landings
• Driveways and walkways
• Easements and other relevant property details

You may also find our guides on permit site plan checklists, site plans versus surveys, what permit reviewers check and why site plans get delayed helpful.

Check your local deck-permit requirements and setbacks before ordering materials or digging footings.

Sources

1. City of Minneapolis — Decks and Building Permits for One- and Two-Family Dwellings
2. City of Austin — Work Exempt From Building Permits
3. Seattle Department of Construction and Inspections — Deck Permits
4. City and County of Denver — Residential Decks, Porches, Patios, Pergolas and Carports
5. City of Portland — Fences, Decks and Outdoor Residential Projects
6. City of Portland — Creating Detailed Residential Deck Plans
7. Montgomery County Department of Permitting Services — Site Plan Requirements for Additions, Decks and Sheds
8. Montgomery County Department of Permitting Services — Residential Deck Guidelines
9. City of Charlotte — Individual Residential Lot Reviews
10. Fairfax County — Zoning and Deck Setback Requirements