My kids moved out of my house and I want to help with affordable housing, so I decided to convert part of our basement to a rental property called an Attached Accessory Dwelling Unit, or AADU. These apartments are good for the environment as they reuse existing buildings rather than requiring demolition and rebuilds. They are also great for affordable housing as they can be added to existing homes without huge expense.

It should have been easy. Our basement already is mostly finished and up to code and we live in Green Lake, near transit. Seattle government also professes to support AADUs and other infill as part of its ongoing land-use reforms. Unfortunately, what we’ve learned is that adding a short-term rental (like Airbnb) is super simple, but adding an AADU for long-term renters is painful, expensive and risky.

For a short-term rental on your property there are no city inspections or standards for renting out your space beyond a minimal cost for registering with the city. Short-term rentals guarantee that tenants will leave when their time is up. Companies will manage the listing and clean the space for you. You even get paid if a tenant can’t make it to your property due to a natural event like an ice storm.

Meanwhile, for an AADU the homeowner must pay many thousands for construction permits and pass inspections before listing their rental. One critical rule is that you cannot put tenants in a finished garage space if you are in a single-family zone, even if removing that parking would create new on-street parking in front of your driveway. A finished garage is often the best space for an AADU as it includes a separate entrance, sound proofing and a large space in which a bathroom could be added. Once you do get a tenant, you are also subject to tenant protection rules that can lead to you living with a problem tenant that you can’t remove.

The result is that there are roughly 4,000 Airbnb listings for short-term rentals in Seattle, but only about 1,000 AADUs have been built since the Housing Affordability and Livability Agenda passed, according to a 2021 city report looking at the period between 2016 and 2021. I have also seen AADUs being built simply as a land-use workaround and then not being rented out, since limits on floor space for new single family homes can be bypassed by characterizing part of the floor space as an AADU.

A few key fixes would make all the difference:

∙ Close the regulatory gap that pushes people to rent Airbnbs instead of taking on long-term renters. Why should homeowners have all the power if a tenant stays less than a month, but tenants have all the power if they stay for more than a month?


∙ We should reinstate a parking waiver program that would allow single-family homes to not have off street parking provided that they are not in a Residential Parking Zone (meaning there is plenty of street parking available). It can be restricted to situations where there is an affordable AADU being added, or where equivalent on street parking is made available when the off-street parking is removed.

∙ Waive permit fees that homeowners are currently charged for creating AADUs, particularly if the AADU will be affordable or accept tenants using housing vouchers.

∙ Finally, the city should help homeowners find the incentives, permits, contractors, and financing to do affordable AADU conversions. The program could be modeled on the Seattle City Light program called Community Solar, which helped people buy into solar and get panels installed on their roof or in shared locations.

Instead of telling homeowners concerned about housing affordability that they should leave so developers can knock down their home, why not give them a simple and direct way to help out?