Residential Retaining Wall Permit & Inspection Process
A permit is required to install a retaining wall if the height of the wall measured from the bottom of the footing to the top of the wall is over 48 inches, unless supporting a surcharge. A permit application for a retaining wall installed on the private property line must include a letter of approval from the adjacent property owner. Occasionally, lot conditions require approvals from other agencies such as easement holders, or homeowner associations. Any Retaining Wall installed within the County right of way will not be permitted and will be required to be removed. A retaining wall is considered an accessory structure if it exceeds the height of 6' 6”.
A permit is required to install a retaining wall if the height of the wall measured from the bottom of the footing to the top of the wall is over 48 inches, unless supporting a surcharge. Section R404 of the residential building code requires retaining walls that retain more than 48 inches of unbalanced soil or retaining walls exceeding 24 inches in height that retain additional loads in addition to the unbalanced soil to be designed by a Maryland State Licensed Design Professional to ensure stability against overturning, sliding, excessive foundation pressure and water uplift. Retaining walls shall be designed for a safety factor of 1.5 against lateral sliding and overturning.
Measurement of Height: Wall height is measured from the lowest level of the grade abutting a wall.
Height and Placement: The maximum height of a retaining wall or wall is 6' 6". Except as follows:
- A wall must not be located within any required drainage, utility or similar easement, unless approved by the agency with jurisdiction over the easement.
- A retaining wall where changes in street grade, width, or alignment have made such structures necessary;
- Any other wall or retaining Wall that is 6.5 feet or less in height and is not on a property abutting a national historic park;
Applications for eligible projects will be taken in and reviewed through the intermediate track process. Other applications will be taken in and reviewed through the regular review process that may take up to 17 days.
Multiple walls or complex applications will be taken in for the regular review process. Regular review track may take up to 17 days.
Please refer to our fee schedule for information about fees associated with this permit application type.
Homeowners may apply for a Retaining Wall permit in their own name; however, if a contractor is to perform the work, DPS strongly suggests that the contractor be listed on the permit as the party responsible for the work. A contractor must have a Maryland Home Improvement Commission (MHIC) license to obtain a permit.
Any dispute as to whether a retaining wall has extended into a neighbor’s property or questions about the location of property lines is a legal matter to be resolved by the property owners.
Please see our list of required inspections associated with this permit application type.