Accessory Dwellings

A one-stop source about accessory dwelling units, multigenerational homes, laneway houses, ADUs, granny flats, in-law units…

How do ADUs affect property values?

Opponents of ADUs frequently charge they will bring down property values for the whole neighborhood. What is the evidence?

July 2, 2014 · 10 Comments

How much do ADUs cost to build?

Some survey results about ADU costs… and some thoughts about why ADU developers aren’t usually real estate “pros.”

June 25, 2014 · 8 Comments

Do ADUs actually provide housing?

It may seem odd to ask whether a housing form actually provides housing, but it’s a key premise in civic debates about accessory dwelling units.

June 18, 2014 · 4 Comments

Why ADUs are hard to study, and confuse nearly everyone

ADUs are a really unusual form of development. This post goes over their special qualities, and explains why a lot of “debate” about ADUs is so repetitive.

June 11, 2014 · 11 Comments

Research and policy about accessory dwelling units: introducing a 13-part series

Which hopes and fears about ADUs are most likely to be true? Explore claims and controversies with new evidence, in this 13-part series, beginning today.

June 4, 2014 · 19 Comments

Repost of Little Pink Houses: Debate Regarding Zoning Laws and Accessory Dwelling Units Getting More and More Relevant

We thought this National Law Review article was interesting because it deals with the legal issues that ADUs confront in municipalities around the US. You can read more about how … Continue reading

May 12, 2014 · Leave a comment

City of Portland ADU Permit Trends

The City of Portland continues to grow its ADU housing stock.  In 2013, there were almost 200 ADU permit applications received, which is about 25% of all single-dwelling permits in Portland.  … Continue reading

March 12, 2014 · 5 Comments

ADU Case Studies Project Launch

In the summer of 2013 Oregon DEQ conducted a survey of Accessory Dwelling Unit (ADU) owners. We received an excellent response from across the state and have published the ADU … Continue reading

December 28, 2013 · 3 Comments

ADU owners: take this survey from students at UC Berkeley

Hey folks, if you aren’t familiar with New Avenue Homes, you should be.  They’re a developer/builder that has created dozens of ADUs in the Bay Area, and their CEO Kevin … Continue reading

November 14, 2013 · Leave a comment

ADU Survey Report Published

A survey of ADU owners in Portland, Eugene, and Ashland, Oregon is complete and now published.  You can find it at Oregon DEQ’s website and AccessoryDwellings.org.  This mail and web survey … Continue reading

October 4, 2013 · 6 Comments

ADU Survey is underway!

A new survey of ADU owners has been mailed to over 900 ADU owners in Portland, Eugene, and Ashland, Oregon. The purpose of this survey is to better understand how … Continue reading

June 8, 2013 · Leave a comment

Do lax “granny flat” regulations encourage absentee landlords? Some new evidence from Portland.

Imagine, in the abstract, the absentee landlord. I personally see him as a sort of Dickensian villain, say Sir Mulberry Hawk, coarse in intention despite his fine clothing and mustache, … Continue reading

May 29, 2013 · 6 Comments

Discreet Density

Skinny homes on 25’ wide lots.  New apartment buildings without off-street parking.  Bulky 2,500+ sq. ft. ‘traditional craftsman’ homes popping up all over the inner-east side.  These are Portland’s most … Continue reading

May 4, 2013 · 9 Comments

Why Are Permitted ADUs So Rare?

From Washington DC to Vancouver BC to Boston, MA, there are more and more examples in the media of individuals attempting to build and live in smaller dwellings and in … Continue reading

March 30, 2013 · 5 Comments

Zoning Regulations for ADUs in 55 West Coast Cities

Oregon DEQ updated our ADU Zoning matrix recently in collaboration with Sightline Institute’s recent Legalizing Inexpensive Housing series.  Read the whole series – it’s great! A few of the cities stand … Continue reading

March 8, 2013 · 2 Comments

Portland extends waiver of SDCs on Accessory Dwelling Units

(Editors note- for the most recent SDC waiver information, read this post. 4/2016)  Great News! This afternoon, Portland’s City Council voted unanimously to extend the waiver of Systems Development Charges … Continue reading

December 5, 2012 · 25 Comments

Multigenerational homes: accessory dwelling units by any other name

In the past year or two, major builders have accomplished an interesting slight of hand.  They have recognized the need for houses with ADUs, and started selling them for tidy … Continue reading

November 30, 2012 · 4 Comments

Appraisal Journal on ADUs: they could be worth more than you think

Today the Appraisal Journal publishes a research paper about residential properties with accessory dwelling units (ADUs).  The paper describes an income-based method for appraising properties with ADUs, and concludes that … Continue reading

November 20, 2012 · 10 Comments

Videos from the Build Small | Live Large Housing Summit

Here are a few of the videos from the Build Small | Live Large Summit. For more videos and presentations, check out the conference home page. The quality of the … Continue reading

November 8, 2012 · Leave a comment

Build Small | Live Large Housing – The Beginning of Something Small

On Friday, October 26th, we held an incredible event at Portland State University. It was the first summit of its kind, focusing on space efficient housing. The Build Small | … Continue reading

November 1, 2012 · 1 Comment

Build Small / Live Large Housing Summit

When measuring energy use on a per sq ft basis, large homes are often more energy efficient. The problem is that energy is actually used on a per person basis … Continue reading

October 9, 2012 · 4 Comments

Why Oregon DEQ loves ADUs

Basic logic tells us that smaller homes use less energy and fewer building materials. How much less? What’s the environmental benefit of small homes? We at the Oregon Department of … Continue reading

September 13, 2012 · 2 Comments

The many and confusing synonyms for ADUs

A quick note about language here.  One reason people get so confused, and perhaps heated, about accessory dwellings is that language about them is  confused.  The different names conjure up … Continue reading

June 4, 2012 · 23 Comments

A research and action agenda for Accessory Dwelling Units and their advocates

I spent a lot of 2011 learning about Accessory Dwelling Units (also known as in-law units, granny flats, backyard cottages, etc).  Beat that in terms of geekiness!  (Okay, I bow … Continue reading

January 10, 2012 · 8 Comments

Appraising properties with accessory dwelling units: a preview of new methods and findings

[update Nov. 2012: the paper, including updated results, is out in Appraisal Journal… click here] This year I’ve been working with appraiser Taylor Watkins of problem of appraising properties with … Continue reading

December 21, 2011 · 15 Comments

Dwelling in the Urban Alleys of DC (Part II)

Part One of this post ended with the restoration movement’s success in fending off an outright ban on existing alley dwellings in Washington DC. In this follow-up, I’d like to … Continue reading

December 11, 2011 · 4 Comments

Dwelling in the Urban Alleys of DC

A book review of Alley Life in Washington (Editor note: this is part one one of a two part series. You can read part II here.) Alley Life in Washington … Continue reading

December 5, 2011 · 5 Comments

Portland small home survey

Attention: If you are seeking the Oregon DEQ, Metro, and accessorydwellings.org survey being conducted in June, 2013, please visit http://adusurvey.org/ From garage lofts, to backyard cottages, to yurts, to cute … Continue reading

December 1, 2011 · Leave a comment

“Understanding and Appraising properties with Accessory Dwelling Units (ADUs)” – a free seminar December 16, 2011 in Portland

[EDITOR’S NOTE: this event has already occurred! For a synopsis of results, click here.] (for an emailable PDF of this invitation, click here) A presentation for real estate, building, and … Continue reading

November 21, 2011 · Leave a comment

How appraisals and “GSEs” make financing an ADU challenging

(Update January 2013: please note that the research on which the following piece was based has now been published in Appraisal Journal.   Please read the full text of that article … Continue reading

November 21, 2011 · 11 Comments

Can ADUs solve our McMansion problem? Or maybe the other way around?

Accessory dwellings don’t often get a thorough discussion in the media these days, because most writers (and most Americans) are still getting used to the basic idea of them.   We’re … Continue reading

November 10, 2011 · Leave a comment

Why are ADUs such a good idea?

There’s plenty of reasons why ADUs are good for personal and financial reasons, which are described below. But, before we cover that, it’s good to understand the range of reasons … Continue reading

October 29, 2011 · 1 Comment

Energy efficiency and building size

Building residential options that use less energy is achieved most effectively by building smaller square footage units and filling in vacant urban space (aka urban infill). Building green is achieved … Continue reading

October 29, 2011 · Leave a comment