Kirkland, WA Fence Regulations: Retaining Walls (2026)

115(3)(g) governs every rockery and retaining wall built in a required front, side, or rear yard in Kirkland. The base rule: a maximum of four feet high, measured in the required yard. If a fence stands within five feet of the wall, the two structures are treated together and their combined height cannot exceed six feet, whether the fence sits on top of, below, or beside the wall. The Planning Official can approve a modification above these limits only when the size, configuration, topography, or location of the lot makes it necessary, and one of two design conditions is met: the wall includes terraces deep enough to hold vegetation or otherwise reduces its visual mass, or the modification will not have any substantial detrimental effect on abutting properties or the City as a whole.

For the combined fence-and-wall limit specifically, a modification is also available where an open guard railing is required by the Building Code and kept at the minimum height the Building Code demands, or where the fence portion is designed no more than 50 percent solid alongside a terraced wall. 115), which controls what can occupy a setback area citywide; retaining walls are addressed as one of nineteen enumerated categories of structures and improvements allowed in yards. Property owners planning a wall near a required setback line should confirm both the four-foot base limit and the five-foot proximity trigger for the combined cap before pouring footings, since the City measures the two structures together rather than independently once they sit close to each other.