91视频

The concept of an accessory dwelling unit may be straightforward, but that doesn’t mean development is a simple process.

The city of Portland’s Bureau of Development Services, on its website, defines an ADU as 鈥渁 second dwelling unit created on a lot with a house, attached house or manufactured home.鈥� Such a unit can take the form of a converted garage (or other house section), an addition or a separate building. ADUs often are used to house aging family members or yield income through rents. But appraisers say the structures raise significant questions that remain to be answered.

鈥淭he idea seems simple enough, but the practice of actually getting an ADU built, financed and appraised is very complicated at this point,鈥� said Taylor Watkins, owner and principal appraiser of Watkins & Associates, a Portland-based residential appraisal firm.

Watkins recently teamed with Martin Brown, a freelance writer, researcher and ADU advocate, to conduct a study that they hope will shed light on some of these challenges.

鈥淎 lot of professionals within the real estate industry 鈥� brokers, appraisers and lenders 鈥� don’t understand what (an ADU) is. When it comes to buying or selling properties that have them, they really don’t know what to do,鈥� Brown said. 鈥淭he confusion in that regard contributes to a lack of ADUs being developed.鈥�

Funded in part by a $10,000 grant from the Appraisers Research Foundation, Watkins and Brown set out to compare two different ways of valuing homes with ADUs. Their hypothesis was that the existing method undervalues the properties. Because so few ADUs exist, appraisers struggle to use the standard valuation method 鈥揷omparing to similar properties nearby that sold recently. So Watkins and Brown used an approach commonly used in commercial real estate called 鈥渧aluation by income,鈥� which creates a value for a property based on potential rent.

The study looks at the actual sale prices of 18 recently sold, single-family homes with ADUs in Portland, and compares them to valuations based on potential income through renting. Watkins and Brown expect to finish their analysis in the next month and then publically present their findings.

鈥淲hat everyone would really like to know is how having an ADU affects the ultimate sales price of a property,鈥� Brown said. 鈥淚f our systematic estimation of value ends up differing from the sales prices we observed, it will be helpful to all sorts of real estate professionals, and eventually filter down to homeowners.鈥�

Meanwhile, appraisals of ADUs become more difficult because of design and construction innovations. Dan LaJoie, architect and owner of Departure Design, said that one of his clients is considering using manufactured housing as an ADU because of construction cost savings.

鈥淚t’s an intriguing approach,鈥� LaJoie said. 鈥淏ut we are stepping back and looking at whether this is the right thing to promote as a firm. They would be built in factory conditions, but within a 500-mile radius, which is a good thing.鈥�

Since Jan. 1, the Bureau of Development Services has received 75 applications for ADUs.

These days, an increasing number of contractors are looking to build the structures. Joe Robertson, owner of Portland-based Shelter Solutions LLC, has constructed ADUs since 1998. He advertises his expertise on the company website, noting that he will help clients navigate the approval and permitting process, which can be 鈥渃onfusing and overwhelming to the inexperienced.鈥�

鈥淚’ve noticed a lot more competition 鈥� it’s a good little market, and remodeling is getting tighter and tighter, so more of those types of contractors are moving into the ADU market,鈥� Robertson said. 鈥淎nd I welcome it because I think the more, the better. As soon as one gets built in a neighborhood, I get three or four other inquiries.鈥�