Building permit plans

Guide
Get general information about the plans you need for most building permits for work on a house or duplex (residential). Viewing our sample floor plan, sample foundation plan and sample site plan can help you get started.
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This webpage is about plans you need to accompany a building permit application.

Please talk with one of our plans examiners for help with building plans. You can book a free 15-minute appointment for more information.

Preparing your plans and minimum submittal requirements

Apply online: One set of plans is required when you apply for a building permit online.

Apply in person: Four sets are required when dropping off plans in person. One set will be stamped approved and returned to you to keep at the job site. 

A copy of your approved plans will become a permanent record with the City of Portland.

  • Check records for work permitted in the past. You may be able to find drawings on file for work done after 1976.
  • Anyone can draw residential plans. The plans must include straight lines and precise measurements. Plans must be drawn to scale.
  • Get the complete list of minimum submittal requirements for residential projects (what you must include for a complete application)

Items usually required for a complete building permit application

Typical plans include:

  • Site plan
  • Floor plans
  • Elevation views
  • Cross sections and detail drawings
  • Your plans must clearly show all the work you intend to do on the building.
  • Clearly defined existing conditions and new construction
  • Information about where the building sits on your property. The plans need to show the building in relationship to property lines and other buildings on the site.

Also:

  • The plans must be on substantial paper. Scanned plans must be high-resolution.
  • Drawings may not contain color.
  • Permanent black ink must be used.
  • Clear black and white photocopies are best.
  • Please do not turn in a tracing paper original.
  • Line quality and contrast must be easy to read and strong enough to scan.
  • Photographs cannot be part of the plan.
  • Use 12-point font for all dimensions and notes.

All plans must be drawn to scale.

  • 1/4 inch = 1 foot is the most common scale used for residential floor plans and section views.
  • 1 inch = 10 feet is the minimum scale accepted for site plans.
  • The scale used must be clearly shown and the site plan must show the entire lot.
  • Building elevations must be to scale and show the slope of the ground adjacent to the building.

Site plan

A well-prepared site plan is the most important document to include with your application. All major review groups need to approve your site plan. Site plans must be easy to read and copy. A complete and accurate site plan will speed up your permit application reviews. It also means less requests for missing information, which can delay an application.

Use the Sample Site Plan to help you prepare complete site plans for your project. Check out the sample site plan here:

Visit the guide to the Sample Site Plan: Drawing a site plan.

Floor plans and foundation plans 

A floor plan, also known as a plan view, is what you would see if you were to look straight down at a floor or basement with the roof or floors above removed. You will need to provide a roof plan and one floor plan for each level of the building on which work is being done, that clearly shows existing and proposed work. Also:

Sample floor plan drawing shows bedrooms, bathroom and inside and outside walls
  • If you are constructing a new building or an addition, you will also need to provide us with a foundation plan. This plan should show the layout, dimensions and details of continuous concrete slabs, footings, reinforcing steel, and the strength of the concrete to be used. The location of the crawl space access and the foundation vents must also be shown. 
  • A floor plan for each level of the building being constructed or remodeled must show the location of all full and partial height walls, the size and proposed use of all rooms affected by the work and a north arrow.
  • The location, size and type of each window must be shown on the floor plan.
  • The location of bearing walls, headers, beams, and other structural members supporting loads from above must also be shown on the floor plans or shown on separate framing plans. Floor plans must show all steps and stairs.
  • Plumbing fixtures, heating and cooling equipment, electrical outlets, switches, etc. are typically shown on the floor plan, but can be shown on separate plans.
  • The floor plan must also show the location of all smoke detectors. 
Sample foundation plan shows foundation detail and details foundation requirements

Section drawings 

Section drawings, sometimes called cross sections, are what you would see if you cut vertically through a building from the tip of the roof down through the ground, and then looked at what the cut exposed. Include gutters and downspouts. Also:

  • Section drawings are a useful way of displaying structural information and information about construction materials that are needed to do our code review. Full sections for residential construction are usually drawn at a scale of at least 1/4 inch = 1 foot and wall section and details at a scale of least at 1/2 inch = 1 foot. Partial sections may be drawn at a larger scale to show something in detail such as footings, overhangs and stairs.
  • To get a building permit for new construction or an addition, you must provide section drawings that show typical building conditions.
  • For simple projects, a single section drawing showing each of these items:
    • the size of the footing and the distance between ground level and the bottom of the footing
    • the size of the foundation wall and how high it will rise above the ground
    • the size and spacing of structural members such as beams, joists, studs and rafters which are not shown on other drawings
    • wall, ceiling and roof coverings and finishes
    • wall, floor and ceiling insulation
    • ceiling heights
    • eaves, decks and other projections 
Sample section plan shows a cross-section of a building from the roof to the ground and items inside and outside the view
  • For more complex buildings or additions, full sections through the work in multiple directions and at different locations may be required to fully explain the work. Separate structural section drawings or details may be required, in addition to building or architectural sections, to show the structural connections.
  • For buildings containing new or revised stairways, stair details must be provided which indicate the construction materials, structural support and dimensional relationships to surrounding construction.
  • The purpose of building plans is to provide the City of Portland with a complete and accurate description of your proposed project. If there is something you think you will need to explain, please put it on the drawings.

Building elevation drawings 

Building elevation drawings are exterior views of the building, sometimes identified as front, rear, left, right; or north, south, east, west. Any project that requires a change in the exterior of the building must have building elevation drawings.

Elevations must be drawn to scale, 1/4 inch = 1 foot is the normal scale. 

Building elevation drawing shows an outside view of a home including the north and west viewpoints

Elevations show the level at which the ground meets the building, the slope of the ground where it meets the building, the vertical location, size of windows and doors, the type of siding and roofing, the height and configuration of guardrails and similar features on the exterior of the building.

Making changes to approved plans

After you begin work, you may need to make changes to approved plans. To change approved plans, you need to show the changes on a new set of plans. Submit them online using DevHub or bring three new sets in person along with the stamped/approved set of the original plans. Then, a plans examiner and city planner will review your changed plans.

Please do not mark up the originally approved set! If we approve the changes one stamped plan set will be returned to you to keep with the original plans.

More tips for a complete site plan and architectural plans

  • Verify utility locate information with actual location of service connections before you draw them on the plans.
  • The permitting process will move along more efficiently with complete and accurately prepared plans. 
  • Requesting the latest submittal requirements for each type of residential project is a good idea.
  • All drawings/plans must be executed in the designated scale and the scale must be shown on the drawing/plan.
  • Plans must be on substantial paper and in black ink. A crisp photocopy is acceptable.
  • Use the checklist to make sure that you include all required items on your site plan.
  • Simple projects may only need a single section drawing; more complex projects will require full sections and multiple views.
  • If you have questions, concerns or need help, schedule a 15-minute appointment

This webpage is also available as a PDF: