How to Refinance an Accessory Dwelling Unit
In the past, issues with valuing Accessory Dwelling Units (ADU’s) have been quite common. Refinancing an ADU is one of those black boxes that appraisers, underwriters and banks don’t know how to correctly handle.
Green Mortgage Northwest recently had a great success with a specific technique developed by Taylor Watkins, a local Portland appraiser, and Martin John Brown, with some funding from Portland Metro. It relies on the income valuation approach, which treats the ADU as an income-producing property rather than a shed, garage or other structure that doesn’t add much value to a property compared to a building that can potentially add hundreds of dollars a month to the owner’s cash flow.
At Green Mortgage Northwest, we contract with an Appraisal Management Company that is local. That allows us to request that certain green-educated appraisers be added to their roster of appraisers. Rather than bringing in someone from out in the suburbs to value a property in Hawthorne or Alberta, a local appraiser with a knowledge of green building and the latest valuation techniques can be called upon.
We can’t specifically request a certain appraiser to value ADU’s. However, here’s what we CAN do for green properties:
- We CAN request a green-educated appraiser. We have about five of them, including Taylor Watkins.
- We can also request that the appraiser calls to speak with Taylor regarding the correct way to value ADU’s and that the appraiser reviews the report Taylor put together. How much reading they do, we can’t control…
- It is a slight crap shoot because the mortgage broker can’t affect the valuation of the property or choose a specific appraiser. However, we just had a great recent victory with a ADU owner in Portland who runs www.accessorydwellings.org. The latest blog post goes into this process in detail (this is a synopsis).
A few best practices:
- Request a green appraiser when ordering the appraisal.
- Attach a few guides for the appraiser’s convenience along with some back history on the project.
- Let the appraiser know the property can be financed as either single family or multi-family, depending which nets the highest value.
- Make sure the appraiser knows this is a legal, permitted, habitable, ADU as defined by the City of Portland Bureau of Development Services. You can even link to Portland Maps to show the certificate of occupancy.
There is a necessary set up with underwriting to make sure expectations are clear regarding the type of property and other requirements. We’re here to guide you through that!

