What to do if you have an ADU, but no permits

Tips From a Compliance Officer on Legalizing an Unpermitted ADU

Realtors and County staff across the region talk with folks every day who are considering permitting an existing ADU. Here are some things they have learned:

Talk to local staff. You usually don’t have to give an address, just a general description of your situation to learn more. You can always ask how unpermitted ADUs are handled first, since this might vary based on where you live. Some areas might have programs or resources to help you decide if it’s possible too.

Consider hiring a professional. Navigating regulations and permitting can be complex. Trying to do it yourself is often more expensive in the end, especially because each round of reviews costs more. A professional will know the rules and can manage the application process, saving you time and money.

Build a budget and be strategic. The costs can add up quickly when legalizing an unpermitted ADU and at some point you will need to make a go/no-go decision on if it’s feasible. Figure out the sequence of steps, identify what is necessary for legalization, list out expected costs, and decide how to finance it.

Gather documentation. Some jurisdictions allow homeowners to use the building standards in place when the ADU was built, so figure out how you will prove the construction date. Did you save receipts? Are HVAC components dated? Does the assessor have records? Do you have a dated aerial image?

Prepare for a marathon, not a sprint. Other issues can come up that increase time and costs, like driveway modifications or lot line adjustments with a neighbor. Don’t let the bumps in the road stop you once you’ve made a ‘go’ decision, just take a breath and keep going.

An unpermitted ADU can be more expensive than bringing it up to code. If the ADU was well built, costs are usually fees for drawing, permits, and (maybe) impact fees, plus future taxes from property value increase. The costs of NOT having a legal ADU could be a lot. Insurance companies refuse claims for unpermitted structures all the time, and fines for code violations can be heavy.

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