What terracing actually does
Terracing splits a slope into flatter benches held by retaining walls. Each bench can be used. Each wall still has to hold the soil and send water somewhere safe.
A single wall holds one grade change. A terrace stack is a system. Water on an upper bench can load the wall below. Compaction on one bench affects the next. Ask the designer to treat the slope as one project.
How the City treats stacked walls
Inside City of San Diego limits, Information Bulletin 220 has a specific trigger for tiered walls. A permit is required when the height from the bottom-tier wall’s top of footing to the top of the top-tier wall is greater than six feet, or when the footing of any tiered wall crosses the slope stability plane of a lower-tier wall. Those planes are assumed to project upward from the bottom edge of each footing’s heel at 2 horizontal to 1 vertical.
That is two independent tests. A short pair of walls can still need a permit if a footing crosses that plane. Confirm the section drawing, not the visible face.
Other jurisdictions set their own rules. Confirm with the department that serves the parcel.
Drainage across the benches
Each wall still needs an outlet. The City’s standard masonry design, where it applies, prohibits discharging wall drainage onto an adjoining property. A terrace that weeps onto the bench below without a collection path is incomplete. See drainage and the hillside page.
We do not publish a San Diego price for a two-tier or three-tier system. Compare written scopes for the same heights, benches, drainage, and permit path.
Next step
Wall Pro SD connects homeowners with licensed local crews. Call (858) 400-4639.
See terraced garden walls and drainage solutions for retaining walls.