Do I need a permit for a retaining wall in Virginia?

The statewide rule

Virginia's building code lists the work that needs no permit. For retaining walls, the exemption reads: "Retaining walls supporting less than three feet of unbalanced fill that are not constructed for the purpose of impounding Class I, II, or III-A liquids or supporting a surcharge other than ordinary unbalanced fill."^[1]

In plain terms, a wall needs a building permit when either is true:

• It holds back three feet of soil or more. Unbalanced fill is the difference between the ground level behind the wall and in front of it. Prince William County defines wall height as the difference in grade level on either side of the wall at a specific location.^[6]
• It carries a surcharge. A surcharge is extra load above the wall beyond the soil itself, and Fairfax County gives a driveway or patio as examples.^[2] A wall with one is outside the exemption whatever its height.

Two more points from the same section: the exemption does not excuse the wall from the code's other requirements,^[1] and if an owner asks for a permit for exempt work, the building official issues one and the related inspections apply.^[1]

Fairfax County

Fairfax County lists retaining walls holding less than 3 feet of earth among work that needs no building permit, as long as the wall has no added surcharge such as a driveway or patio above it and is not tiered.^[2] Above that, the county has two permit types. A residential retaining wall permit covers walls retaining more than three but less than four feet of earth that are non-tiered, non-stacked and non-segmental, with level backfill and no surcharge, and walls retaining over four feet need a commercial retaining wall permit.^[3]

For the simplest walls, the county's Typical Retaining Wall Details can be used instead of drawn plans.^[3] Projects in the towns of Clifton and Vienna need separate approval from the town.^[3] Grading has its own rule: land disturbance of 2,500 square feet or more needs an approved site-related plan before work starts.^[4]

Prince William County

Prince William County requires a building permit for all retaining walls supporting more than three feet of unbalanced fill, and for a retaining wall of any height that supports a load from a structure above it, such as a wall, road, driveway or sidewalk.^[5] Terraces count together: a tiered system needs a permit if the upper wall is within two times the height of the lower wall and the whole system is at least three feet tall.^[5]

Separately, zoning approval is always required for retaining walls, whether or not a building permit is.^[5] The county's guidelines say the Zoning Division checks the wall against required setbacks and may refer it to watershed staff to make sure it will not cause drainage problems for neighbours or for your own lot.^[6] The same retaining wall guidelines add that walls with an exposed height of 24 inches or more must be engineered if they carry a surcharge or sit on problem soil,^[6] and a wall built on problem soils has its foundation inspected by an approved licensed private geotechnical engineer.^[6]

Everywhere else

Prince William County notes that all jurisdictions in Virginia are required to use the Uniform Statewide Building Code,^[5] so the three-foot and surcharge rule is the starting point wherever you live, including the New River Valley and Roanoke. What varies is everything around it: zoning setbacks, grading and erosion rules, floodplain and stream buffers, and how tiers are measured. Call your county or city building department, or your town if it runs its own, with the wall's height, length, location and what sits above it.

Two other checks apply everywhere:

• Your HOA. Prince William County also reminds owners to check with their homeowners' association, whose covenants may require approval for exterior work.^[5]
• The 811 call. Virginia law says no one may begin any excavation or demolition without first submitting a locate request to the notification center.^[7] That covers digging the base and removing an old wall.

Who pulls the permit

In Fairfax County, property owners may obtain permits in their own name, but the county strongly recommends that a properly licensed contractor pull them,^[3] so the county can better help get defective work corrected.^[3] Virginia's residential contract rules require a statement of assurance that the contractor will comply with all local requirements for building permits, inspections and zoning,^[9] so ask to see that line in the contract. What building a retaining wall involves walks through the inspections a permitted wall goes through.

When to call a licensed pro

A wall that needs a permit is a wall that needs a licensed contractor, and often an engineer. The Board for Contractors says work valued at $1,000 or more requires a valid Virginia contractor's licence in the right category,^[10] and Virginia's landscape service contracting specialty (LSC) includes construction of retaining walls for landscaping purposes.^[8] Masonry and concrete contractors also build them. Check the licence before you sign, and see what a retaining wall costs for how permits and engineering show up in a quote. For a driveway or apron project next to the wall, the driveway permit answer covers the right-of-way side.

Loclis lists DPOR-licensed businesses with their licence number and class. Browse retaining wall businesses, look up concrete and hardscaping contractors in Blacksburg, or see all concrete and hardscaping answers.

Describe your wall once and licensed local businesses quote, permit included.