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Project Guide For Retaining Walls

This guide is intended to provide you an overview of the permitting process for retaining walls. 

Zoning permits: A zoning permit is required to construct or alter any retaining wall that is over 12 inches in height, measured from the ground.

Building permits: A building permit is only needed for retaining walls that are over 4 feet in height, measured from the base (even if the base is below grade). Retaining walls 6 feet tall or taller require commercial engineering review. Retaining walls of any height in a landmark or historic district must apply to Landmark Preservation.

NOTE: All retaining walls or fences must be six inches back from the public sidewalk, regardless of where the property line is.

Looking for information on fences?  See the Project guide for fences.

Help Me Get Started . . .

Before you start your project, you need to know what regulations apply to your property and what factors may impact your project. You'll need to consider:

Historic Landmark Status

Any project that involves changes to the exterior of landmark structures or properties in historic landmark districts must be reviewed by Landmark Preservation staff before you begin. The appropriate zoning, building, curb cut, or revocable permits needed for the project will be issued only after design review has been completed and the project has been approved. To determine your property’s landmark status, use the DevelopDENVER tool to the right. Then, visit the design review web page for more information.


Zoning establishes standards for things such as the size and location of structures and acceptable uses for your property. Before you begin construction, you need to be sure your project is in compliance with the Denver Zoning Code. Use the DevelopDENVER tool to the right to determine the zoning for your property. In the results, click on your zone district for descriptions and definitions; then, click on your neighborhood context for more information on zoning in your area. 


Any project that encroaches on a designated parkway setback will need to undergo parkways review. Certain parkways and boulevards are specifically designated by ordinance to preserve their unique character. Each designated parkway has its own right-of-way width and regulations of setback distance of structures and signs. If you are unsure if you live along a designated parkway or for your parkway’s specific regulations, enter your address into the DevelopDENVER tool at right. Look under “Designated Parkways” on the results panel on the left. If a specific parkway appears, click on the “Details” button for information on setbacks.

Building Code

Denver Building Code provides minimum standards for building in order to safeguard public safety, health and welfare. The permitting and inspection process ensures that all home projects meet these standards and that all dwellings are safe and habitable at the time of construction.

Location of Existing Sewer Lines

If you plan to build a new structure over or within 2 feet of the existing sanitary sewer, you will need to replace the sanitary sewer with approved materials. A plumbing contractor can help you locate the sewer lines on your property. Visit Wastewater Sewer Use and Drainage Permit (SUDP) for application, guidelines and other specific information. Contact the Department of Public Works at 303-446-3759 for additional details.


Transportation review and approval is needed if you are changing the location of any driveways that connect to public streets or proposing improvements, such as changing the curb cut, within the “right of way” (ROW), which includes public streets and sidewalks. All ROW projects must be performed by a licensed contractor and in full compliance with the City Charter, ordinances, permitting processes and all other applicable standards, specifications and requirements. Licensed contractors can obtain ROW permits at Public Works Permit Operations, 2000 West 3rd Avenue, or directly from the ROW inspector at (303) 446-3469. NOTE: Alterations to a driveway that connects to an alley, instead of a public street or sidewalk, do not require transportation review.

Location of Utilities

When designing your project, you need to know where utilities are located. You cannot build over existing utilities. Before you dig, contact the Utility Notification Center of Colorado at 1-800-922-1987 or 811 to mark underground utilities for your project.

Listed in the order they must be obtained. All permits must be in hand and at site before work may begin.

  1. Current City of Denver Contractor’s License/Affidavit of Requirements for Owner-Occupier Permits. See Issuance of Owner-Occupier Permits (PDF) for more information.
    NOTE: ROW improvements must be performed by a licensed contractor.
  2. Landmark Certificate of Appropriateness – if the project is in a designated historic district or landmark property. Visit the Design Review web page for more information.
  3. Parkways Review – if property is on a designated parkway and retaining wall encroaches on setback
    You will need: A completed Parkway Exception Request form and a site plan that includes property lines, parkway setback from property line, proposed type, location and dimensions of encroachment into parkway setback, location of existing residence on property and labeled streets. To get a copy of the form and additional information, contact

The above must be in hand before you apply for the following:

*For a complete list of required documentation for zoning and building plan review, download the Residential Permitting Guide (PDF) for new construction, addition or change of occupancy work.*

  1. Zoning Permit (Single-Family Home & Duplex Walk-Through)* – if the retaining wall is taller than 12 inches, measured from the ground
  2. Building Permit (Single-Family Home & Duplex Walk-Through)* – if the retaining wall is taller than four feet, measured from the footer
  3. Wastewater Sewer Use and Drainage Permit (SUDP) (Plan Review) – if your property is in a floodplain or if you are digging within 2 feet of sewer line
    Visit the wastewater permits page for application, complete submittal requirements and guidelines, and other information.
  4. Major Encumbrance Permit - if the proposed retaining wall is located within the right-of-way
    Contact Public Works Plans Review Services at 720-865-2782 or, or visit the Department of Transportation & Infrastructure's Right of Way Services web page for submittal information.

SUDP application and materials may be submitted by email (, online via e-Plan or in person at the Development Services Permit Counter. Sign in online once for SUDP permit (SUDP).

Zoning and #1R permits may be applied for on the same day. 
Check in online to the Single-Family Home & Duplex Walk-Through line at the permit counter before you arrive, whether you need one or both permits.

Estimate Fees
Zoning and Building permit fees are based on valuation of the work to be completed including the labor and materials. For Wastewater, there is a $100 application fee plus appropriate fees. The fees change yearly. View the permit fee schedules to estimate the fees required for your project. There are no fees for Landmark or Parkways review.

NOTE:  When a Same Day Review is required for the #1R Permit, a  "walk through" submittal fee of 20% of the valuation of the work to be completed with a $100.00 minimum will be charged in addition to building permit fees.

Pay Fees
Fees can be paid in person at our cashier on the 2nd floor of the Wellington Webb Building. We accept Visa, MasterCard and Discover Card, cash and personal checks at our counter.

To pay by mail, send a check to:
Development Services
Wellington Webb Municipal Building
201 W. Colfax Ave., 2nd Floor
Denver, Colorado 80202

All approved construction set of documents, permits and inspector signature card are to be available on site upon request.

Typical inspections during construction of a retaining wall include the following:

  • Footing
  • Foundation Wall
  • Final Inspection
  • Denver Forestry


NOTE:  The inspections listed above may vary depending on the complexity of your project. You will be advised as to which inspections your project requires through the permitting process and by your inspector.

Who Will Be Doing the Work?

Decide whether you plan to complete the project yourself or hire a licensed contractor to complete the job for you.

Do It Yourself

Do-It-YourselfYou may need to pass a Home owners exam  to demonstrate proficiency in specific trades in order to get a permit to do the work yourself. 

You will also need to meet a set of requirements established by the Denver Building Code and the Building Department Policy ADMIN 131.3 governing homeowner completed work.  This policy can be found on our Building Codes, Forms and Policies page. 


Contractors Use the Contractor license search to see if your contractor has obtained a contractor's license from the City and County of Denver. 


To view other considerations, see our Doing the Work Yourself page.

Home Projects

Every project is different.  Depending upon the complexity of your project, the permit requirements and inspection process may vary from the information presented in this guide.  If you have any questions, please contact us.


What you need to know for your project!

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View property details including zoning, landmark status, inspector districts and more.