Concrete Retaining Walls in Lynnwood, WA

Retaining walls in Lynnwood: what to know

The state rule measures height from the underside of the footing up to the top of the wall, so the section starts with the footing depth. Four feet or less, with no surcharge and no impounded liquid, keeps a wall inside the building-permit exemption. A bank, a driveway, or a structure pressing on the wall’s back face counts as a surcharge, and that removes the exemption even for a short wall.

Cutting the ground for the footing is a grading question. The Public Works checklist starts a grading permit for a cut deeper than two feet or a cut slope steeper than 1.5 to 1, and it asks for a drainage plan with no impact on adjacent properties. Water collected behind the wall goes to an outlet placed on the section, and LMC 13.45.040 governs which discharges may enter the storm system.

Permits and rules in Lynnwood

Before quoting, we check the footing depth, any surcharge, and the grading triggers against the wall as drawn. We confirm the current zoning height rule for the parcel with city staff, since the zoning text on the city’s code site carries an expired date of June 30, 2025. We also confirm whether the counter wants stamped plans for any wall outside the exemption. Stamped engineering is arranged through a Washington-registered professional when the city asks for it.

Rules change and vary by parcel, so we confirm the current requirements with the city before we start.

How we approach it

Record the footing depth on the first drawing
Name every surcharge, from a bank to a building
Place the drain outlet on the wall section
Bring in a registered engineer when the counter asks for sealed plans

For the full process, see our Retaining Walls page.

Building in the cold months? See our guide to winter concrete pours.

Our retaining walls work, serving Lynnwood

Examples of our work. We build retaining walls in Lynnwood and the cities around it. See all of our work

Questions from Lynnwood homeowners

Does Lynnwood’s zoning text limit how tall a retaining wall can stand?

The city’s zoning text on its code site caps retaining walls at four feet above ground where seen from a street or residential zone. That text carries an expired date of June 30, 2025, so the parcel’s current zoning height is confirmed with staff. The building-permit exemption is a separate question, and it reaches walls no taller than four feet that carry no surcharge.

Does a Lynnwood cut for a wall footing need grading review?

The footing cut is measured against the grading triggers: a cut deeper than two feet, or a cut slope steeper than 1.5 to 1, starts the permit. The wall’s own exemption is a separate question, so both are checked before a design is set.

Where does water behind a Lynnwood retaining wall go?

To an outlet the storm rules allow, placed on the section so it does not wet a neighboring lot or the foundation. LMC 13.45.040 allows clean groundwater and footing drains into the storm system unless the director finds a pollution risk, and the outlet is confirmed before the wall is designed.