Why retaining wall permits get rejected

Why do retaining wall permits get rejected?

Because a retaining wall is judged on what you cannot see. A fence is checked on a site plan; a retaining wall is checked on a section drawing, the slice through the footing, the drainage, the reinforcement and the soil behind it. Building departments that publish retaining wall handouts list exactly what they expect, and a wall that comes back with corrections almost always misses one of those items.

1. The height was measured from the wrong place

The model code's 4-foot threshold is measured from the bottom of the footing to the top of the wall^[1], and Saint Paul, Minnesota, applies its permit requirement when the wall is taller than 4 feet at any point^[3]. An application that measures the visible height, or the average along a sloping wall, understates the wall. The code measures from the bottom of the footing, and Saint Paul at any point along the wall.

2. A surcharge nobody showed

The 4-foot exemption only holds for walls that support no surcharge^[1]. Lake Stevens, Washington, counts as surcharge any load in addition to level grade within a 45-degree line from the bottom of the footing^[5]; Snohomish County, Washington, gives fill material as an example^[2]. A slope continuing above the wall, a driveway, a patio, a shed or a house close to the top changes everything: Eagle Mountain, Utah, requires a permit for a surcharged wall regardless of its height^[4], and Snohomish County requires engineered plans for it^[2]. Drawings that show the wall but not what is above it get sent back.

3. Engineering missing, or not matching

Many walls need more than a drawing.

• Snohomish County requires engineered plans for walls over 4 feet and for surcharged walls^[2].
• Saint Paul requires a Minnesota-licensed structural engineer whenever the manufacturer's instructions call for engineering, when no manufacturer's instructions exist for the product, when the wall departs from the city's own poured concrete or 8-inch block details, or when the material is not one of those options^[3].
• Eagle Mountain's building plans must include all required engineering^[4].

A stamped design for a different height, soil or layout than the wall on the site plan is the same as no design.

4. No manufacturer's instructions

For block walls, the block system's installation instructions are part of the permit. Saint Paul will not issue a permit until the manufacturer's instructions are provided with the application^[3]. If you bought blocks without them, that is the first document to find.

5. The section drawing leaves things out

Saint Paul lists what a section view must show: the wall material, the footing size and type, the drainage behind the wall (drainage rock, drain tile, weep holes as applicable), any soil reinforcement or geogrid, the slope of the soil behind the wall, and any other detail that matters to the wall's structural integrity^[3]. An elevation must show changes in height and the number of courses^[3]. A sketch with a wall and an arrow saying "gravel" will not pass.

6. On or over the property line

Saint Paul does not allow any part of a retaining wall on or over the property line unless a legal easement agreement has been recorded on all the properties concerned with Ramsey County, and asks to review the agreement before it is recorded^[3]. Eagle Mountain makes retaining walls subject to setbacks^[4]. A wall that holds up your neighbor's yard is also your neighbor's business.

7. Terracing and tiers

Splitting one tall wall into two shorter ones does not always avoid the rules. Eagle Mountain applies specific height and terracing requirements from its development code to retaining walls^[4], and Saint Paul lists tiered wall systems among the scenarios that may require structural engineering^[3]. Two short walls a few feet apart may be reviewed together.

8. Missing site and project information

Eagle Mountain's application asks for the owner, the contractor and the project valuation, a site plan with lot dimensions, existing buildings and the distances from the wall to the property lines with slopes and grades defined, all submitted as PDFs^[4]. Snohomish County bases its plan review and permit fees on the wall's fair market valuation and collects the plan review fee at submission^[2], so a missing valuation stops the file at the counter.

After approval: inspections

Getting the permit is not the end. Lake Stevens says permitted walls often require a special inspections agreement to verify the footings, the drains and the final wall^[5]. Backfilling before the drain inspection hides the one thing the inspector came to see.

If the wall is already built

• Stop-work orders and extra fees. Carmel-by-the-Sea, California, issues a stop-work order for work begun without a required permit, and charges a stop-work investigation fee plus double permit fees before issuing it^[7].
• Legalize or remove, both cost. In New York City, legalizing work done without a permit on a one- or two-family home carries a $600 penalty, and removing it carries the same penalty^[6].

Ask your building department what it needs to see before you decide between legalizing and removing.

How to avoid the corrections

Measure from the footing at the tallest point, draw what sits above the wall, attach the manufacturer's instructions, complete the section, check the property line and the tiers, and get the engineering when the wall needs it. Our permit team prepares that file for your city, with each rule and its link, and tells you at the start when an engineer's stamp is required. The All-in offer adds our review before you file and handles every round of city comments until the permit is issued.

Common questions