Unpermitted ADUs create real risk at sale, refinancing, and with insurance. We manage the complete legalization process — as-built documentation, city permits, required corrections, and final inspection. Detailed written quotes. No surprises.
An unpermitted ADU is any residential structure — converted garage, backyard guest house, basement apartment, or detached unit — that was built or converted without obtaining the required city building permits. It may be a quality structure that's been occupied for years, but without permits it carries significant legal and financial risk.
Norco has a significant inventory of informal structures — converted outbuildings, workshops, and older guest quarters built before modern ADU laws. The city has a defined retroactive permitting pathway.
Three situations make unpermitted ADUs a serious problem:
Legalizing proactively — not under deadline pressure — gives you control over the process and typically produces the best cost outcome.
Here's exactly how we handle unpermitted ADU legalization in Norco:
We inspect the existing structure — workshop, barn, outbuilding, or older guest unit — documenting current condition and identifying all code gaps.
Our architect prepares as-built drawings showing the structure as it exists, required for Norco's retroactive permit process.
For horse-property structures, we verify setback compliance from corrals, stables, and agricultural uses — Norco has specific proximity requirements.
Complete retroactive application submitted to City of Norco with all documentation.
Required upgrades completed — typically egress, electrical, insulation, smoke/CO detection.
City sign-off. Legal permitted ADU. Eligible for rental income, refinancing, and property tax basis adjustment.
The most common code gaps we find in Norco unpermitted ADUs:
We identify every gap during the initial assessment and include all correction costs in our detailed written legalization quote.