urban | design.banter :: More Guidelines for ADU's

Each Friday we bring you  urban | design.banter 
:: infill | re-knitting our urban fabric | cohousing | keeping small towns from becoming suburbs :: why shouldn't where you live be somewhere you would want to visit?

This summer we posted a summary on Accessory Dwelling Units (ADU's): a brief explanation, some benefits, and regulations for Seattle and King County. Below we will outline the regulations for the San Juan Islands.

Accessory Dwelling Units (ADU's) have become more popular and acceptable in the past few years. The City of Seattle began allowing for ADU's in all residential zones (it had previously been only some south Seattle neighborhoods) in 2009. San Juan County allows for a limited number of permits for ADU's each year.

An ADU can be attached, as in a basement apartment, or detached, as in a backyard cottage, carriage house, or alley flat. The implementation of ADU's can fulfill many goals of sustainable development, including density, affordable housing, and smaller house sizes. As our urban fabric is "re-knit", neighborhoods can become more dense, creating more demand for services, therefore creating more opportunities for walkable neighborhoods and less dependence on a car.

Truly sustainable development also includes social goals, many of which are also met by integrating ADU's: a way for homeowners to have a separate income stream, a mix of income and ages; the ability to stay in one neighborhood through varying phases of life, therefore creating lasting community: kids can live in a backyard cottage as they start on their career path, elderly parents or relatives can live in smaller spaces that require less upkeep and be close to their children and grandchildren. The term "mixed income" may be worrisome, but from a social standpoint, renting out an ADU can more successful than an absentee landlord renting a house, in that owners are close to the rental unit, tenants are close to their landlord, so each keeps an eye on each other. The Kentlands Development in Maryland (designed by New Urbanism pioneers DPZ)  is a neighborhood that has successfully integrated market rate, large suburban housing with backyard rental units. An often cited example is of a woman who lived in her ADU and rented out her large house in order to save money and pay off her mortgage.

Anna spoke to BUILDERnews magazine about the benefits of building an ADU or guest apartment. See the article, including photos of two of our projects that include these structures here.

Hare House in Friday Harbor, Second Floor Plan: an apartment over an office and garage can be used for family, or rented out for extra income.

San Juan County:

San Juan County defines an ADU as "a living area that is accessory to the principal residence, located on the same lot, and that provides for sleeping quarters, kitchen, and sanitation facilities. An ADU may be internal, attached or detached."

• The distinguishing characteristic signifying an ADU for the county is a kitchen, even without an oven or stove. A guest or mother in law suite with just a bedroom and bathroom may not be subject to the same restrictions.
• An ADU must not exceed 1,000 square feet 
• There is a limit on the number of ADU permits available, so check with county before moving ahead. The number of detached ADU permits in any calendar year shall not exceed 12 percent of the total number of building permits for new principal residences issued for the previous calendar year. 
• In order to reduce impact, ADU's must be located within 100 feet of the principal residence. 
• Urban Growth Areas and Activities centers generally allow ADU's with less restrictions than rural zones
• A detached ADU is not permitted on parcels less than five acres in size in any rural district, 10 acres in size in the agricultural district, and 20 acres in size in the forest district. Visit the Assessor's Site to find out what zone you are in. 
• Within the Town of Friday Harbor, a detached guesthouse is not a permitted
  accessory structure in Single Family Zones. The Hare House, which is in town and includes a guest house, is in a Multifamily Zone.

 Example home plan, the Pearl Cottage, under 1,000 square feet

Our Home Plan Collection has some great floor plans and designs under 1,000 square feet. View the collection for ideas and inspiration-plans can be customized to meet your needs. 

Next Friday, we'll look at regulations for Bellingham, Anacortes, and Island County. 

 

ADU 101

Accessory Dwelling Units (ADU's) have become more popular and acceptable in the past few years. The City of Seattle began allowing for ADU's in all residential zones (it had previously been only some south Seattle neighborhoods) in 2009. San Juan County allows for a limited number of permits for ADU's each year.

An ADU can be attached, as in a basement apartment, or detached, as in a backyard cottage, carriage house, or alley flat. The implementation of ADU's can fulfill many goals of sustainable development, including density, affordable housing, and smaller house sizes. As our urban fabric is "re-knit", neighborhoods can become more dense, creating more demand for services, therefore creating more opportunities for walkable neighborhoods and less dependence on a car.

Truly sustainable development also includes social goals, many of which are also met by integrating ADU's: a way for homeowners to have a separate income stream, a mix of income and ages; the ability to stay in one neighborhood through varying phases of life, therefore creating lasting community: kids can live in a backyard cottage as they start on their career path, elderly parents or relatives can live in smaller spaces that require less upkeep and be close to their children and grandchildren. The term "mixed income" may be worrisome, but from a social standpoint, renting out an ADU can more successful than an absentee landlord renting a house, in that owners are close to the rental unit, tenants are close to their landlord, so each keeps an eye on each other. The Kentlands Development in Maryland (designed by New Urbanism pioneers DPZ)  is a neighborhood that has successfully integrated market rate, large suburban housing with backyard rental units. An often cited example is of a woman who lived in her ADU and rented out her large house in order to save money and pay off her mortgage.

Anna spoke to BUILDERnews magazine about the benefits of building an ADU or guest apartment. See the article, including photos of two of our projects that include these structures here.

Hare House in Friday Harbor, Second Floor Plan: an apartment over an office and garage can be used for family, or rented out for extra income.

Summaries of Seattle and King County's rules for Accessory Dwelling Units are below. In the coming weeks we will have summaries of the rules of other cities and counties.

Rules for Seattle ADU

View the Backyard Cottage Overview from the City of Seattle Department of Planning and Development here. 

From the overview:

Among those aware of a backyard cottage in their neighborhood:
• 71% said that the backyard cottage in their neighborhood fit in with the surrounding homes.
• 84% noticed no impacts on parking or traffic directly related to the backyard cottage.
• 83% were supportive or strongly supportive of backyard cottage policy.

Highlights from the Client Assistance Memo 116A, "Establishing an Attached Accessory Dwelling Unit (ADU)."

• Backyard cottages, also known as detached accessory dwelling units (DADUs) are allowed citywide effective Dec. 4, 2009
• Seattle Defines an ADU as: a room or set of rooms in a single family home that has been designed or configured to be used as a separate dwelling unit.
• A single family lot my have one ADU or Backyard Cottage.
• An ADU is limited to an area of 1,000 square feet in the single family structure. A unit in a single-family
  home may exceed the maximum size if the structure was in existence prior to June 1, 1999, and if the
  entire accessory unit is located on the same level.
• A parking space for the ADU is required unless it is located in a designated urban center or village, or if the topography of the site or structure location makes it "unduly burdensome."

Rules for King County ADU's

View a summary from the county with links to the code document (summarized below) here.  

• Accessory dwelling units are allowed in all zones in unincorporated King County except Mineral (M) and Industrial (I), provided that certain conditions are met.
• No separate ADU's are allowed on urban lots less than 5,000 square feet, a non-conforming rural lot, or a lot containing more than one
• Either the primary dwelling or the ADU have to be owner-occupied 
• Only one entrance can be located on the street side

Introducing urban|design.banter

A new part of our blog will be urban design banter: infill, re-knitting our urban fabric, cohousing, and keeping small towns from becoming suburbs. 

Our firm's motto of smart growth :: green design means we are dedicated to creating spaces that are not only great to live in but also worthy of visiting. Why shouldn't where you live be somewhere you would want to visit? So many people settle for drab, sprawling, monotonous suburbs, and then save up vacation money and time to walk around cities they find appealing. 

According to Duany, Plater-Zyberk, and Speck in "Suburban Nation: The Rise of Sprawl and the Decline of the American Dream," the majority of time spent at Disney World is not on rides or at shows, but most of the time is spent "enjoying the precise commodity that people so sorely lack in their suburban hometowns: pleasant, pedestrian-friendly, public space and the sociability it engenders." 

In the coming weeks we will be discussing Accessory Dwelling Units (ADU's): where they are acceptable, why they are a good idea, and how they can be implemented. 

Single Family Neighborhoods of the Future (and Past)

Last week I attended "Design for Livability: Sustainable Cities," presented by AIA Seattle, Cascade Land Conservancy & the UW College of Built Environments. Presentations included discussions of Ecodistricts, Eco System services, and health and built environments.

One presentation that I found very relevant was "Transforming Single Family Neighborhoods." Seattle has been feeling this transition for many years with the introduction of infill townhouses, condos, and changes to the code regarding accessory dwelling units. This trend will most likely continue as more people move into cities (about 13% of the world's population 100 years ago, now about 50%) and cities continue to densify. While I believe that this is probably inevitable in order to conserve outlying land (as with the Growth Management Act) and allow for efficiencies in a city, I am a firm believer that this can happen without sacrificing the quality of life of those who live in single family neighborhoods.

Here is a great project presented by Sandy Fischer of EDAW, for Portland Metro's "Integrating Habitat" Competition.

Bungalow Courts (AKA Pine Street Cottages) in Seattle is an example of a pre WWII compact single family neighborhood (10 houses on a 15,000 SF lot) that is once again in fashion, thanks to a revival by developers Kucher/Rutherford. This document by the Housing Partnership, "The Right Size Home," includes this project and is a very comprehensive look at small single family home alternatives around Seattle.