Planning and building an ADU is complicated! There are lots of places to educate yourself though, on-line and around town. Here are a few:


City of Portland ADU Program Guide

-This is a document that the city has put together which distills all the relevant code information for new ADUs or conversions of existing spaces. It is especially valuable for existing spaces as it outlines upgrades you may need to make which are hard to track down otherwise. 

City of Portland ADU zoning code section

- A fairly short read by zoning code standards. This document, along with the building code, governs how and where ADUs are allowed, including the design standards for new ADUs.


City of Portland "conversion to living space" handout

- A useful handout (pdf) that outlines the City's requirements for converting basements, attics and garages to living space and ADUs. Some of this information is in the Program Guide, but this goes into more detail.

-Use this site to find basic info around your property, including lot size, zoning, and the size of the buildings currently on the property.

Bureau of Development Services website

-Find more info about the permit process.

-This is an excellent online resource which showcases and details everything about ADUs in Portland. It includes case studies of many different local ADUs as well as original research about the hows and whys of building them. These folks also put on the 2014 ADU tour which will be reprised in the spring of next year (2015).

Oregon Residential Building Code

-Always wanted to get into the nitty gritty of what is required for a new residential building? Here is your chance to dig in and wade though! 

Portland ADU application package

-This is the paperwork the city requires you to fill out when submitting a new detached ADU. The package has a lot of information and gives one a good sense of what the city is looking for. It is the same process that New Single Family Residences (NSFR in BDS lingo) go through. Requires Adobe Acrobat reader 9+

ADU classes given by Kol Peterson of

-Kol has been offering these extensive day classes for a while now. They typically run through the basics of ADU design and construction with field trips to one or two ADU construction sites. Geared towards homeowners, the class also provides 7 CEUs for Oregon Realtors. 


-Have a specific zoning or building code question you can't find the answer to? Leave a message on one of the above numbers and someone will get back to you within 24 hours.

ADU TOUR 2014 Expert presentations

-This is a series of videos of presentations which were given during the 2014 ADU tour on a variety of subjects. Polyphon gave a talk on small space design which can be seen here.

We hope this provides some useful information and we'll continue to add to this list as we discover new resources. If you'd like a professional take on your ADU project we are always happy to come out and discuss the possibilities with you. Please get in touch!