Puyallup, WA Building Safety: Anti-Mansionization (2026)

Puyallup's zoning code controls oversized homes relative to their lots primarily through a maximum floor area ratio (FAR), the ratio of a building's total floor area to the lot's square footage, set out in row (13) of Table 20.20.020 under PMC § 20.20.020. RS-10 lots are capped at a 0.45:1 ratio, RS-08 and RS-06 at 0.55:1, and RS-04, the smallest-lot zone, at 0.6:1. RS-35, the large-lot zone, carries no FAR number in the table.

PMC § 20.20.028 confirms that this maximum floor area ratio applies only to properties whose principal use is residential, single-family homes, duplexes, triplexes and retirement clusters, rather than to commercial or institutional buildings elsewhere in the code. Because FAR measures total building square footage against lot size rather than footprint alone, it works together with, but differently from, the separate maximum lot coverage percentage in row (11) of the same table and the height limits in rows (9) and (10): a house can meet the height and setback rules for its zone and still be blocked from adding floor area once it hits the applicable FAR.

An accessory dwelling unit does not automatically escape this cap either; ADU floor area is regulated separately under PMC § 20.20.010(11)(e) with its own 1,000-square-foot ceiling, but a principal dwelling that expands beyond its zone's FAR without an approved deviation is treated as a Title 20 zoning violation, enforced through PMC § 20.95.020.