The city of Seattle is changing the definitions of its land-use code to allow more density as well as flexibility in areas designated for duplexes, triplexes, townhouses, apartment buildings, condominiums and other multifamily developments.

Mayor Greg Nickels ordered an update of Seattle's land-use code and, since 2005, the city's Department of Planning and Development has been reviewing the city's multifamily-zone regulations. The review won't affect zoning designations, but it will change their definitions.

Gary Ogden, chairman of the Alki Community Council's land-use committee, is worried about the proposed changes. For example, the city plans to increase the height limit for low-rise multifamily developments from 25 to 35 feet. Ogden is concerned that will result in the loss of views for many established residents.

A multifamily zone is where buildings provide housing for two or more households on one parcel of land. Currently there is a 25-foot height limit for flat-roof duplexes, triplexes, and townhouses. Multifamily buildings with pitched roofs can build to 30 or 35 feet.

Yet flat-roof single-family houses can be 35 feet tall.

"It doesn't make sense to allow a 35-foot height in single-family zones but only 25 feet in multifamily zones," countered Mike Podowski, planning supervisor for the Seattle Department of Planning and Development.

The new definition also will allow less steeply pitched roofs because many multifamily developments were ending up 2.5 stories tall. The change will allow developers to put up fully useable three-story buildings, Podowski said.

Multifamily zones are part of Seattle's land-use code, which was adopted by the city in 1982. Back then the height limit for low-rise multifamily developments was 35 feet, Podowski said. The city revised the multifamily code in 1989 and lowered the height limit to 25 feet.

One reason for re-examining the city's land-use code is to see if it jibes with the Seattle Comprehensive Plan, which was adopted in 1994.

A key part of the Seattle Comprehensive Plan is its strategy for how Seattle can absorb the expected population growth. It encourages new multifamily housing be built in and near established neighborhood commercial areas. That's where goods, services, housing and transportation connections are located.

West Seattle's multifamily zones are found around its business districts as well as along both sides of some of its main arterial streets: California Avenue, Alki Avenue and Delridge Way Southwest.

Beach Drive has multifamily zoning from Alki Point to Me Kwa Mooks Park. There's also a stretch of multifamily zoning on 35th Avenue from Barton to Roxbury streets.

Much of High Point is zoned for multifamily development. It spreads roughly from 27th Avenue to 35th Avenue, and from Juneau to Myrtle streets.

The Youngstown neighborhood south of the Nucor Steel plant is also zoned for multifamily development.

Most of the rest of West Seattle is zoned for single-family houses.

Multifamily zones add up to about 7 percent of Seattle's land area. The city's Comprehensive Plan anticipates there will be 47,000 new households in Seattle by 2024. Many of those people will be living in 7 percent of the city.

"The goal is to create new multifamily zones," Podowski said

The land-use code revision also aims to encourage greater variety in the types of multifamily housing available in Seattle, reduce redundant requirements, and make the code easier to understand.

Developers get incentives from the city if they promise to keep the rent lower for at least a few units to make some housing affordable to low-income tenants. They also get points for using environmentally sensitive building materials and techniques, Podowski said.

The definition of "open space" is another concern for Ogden. Many people think of open space as yards and setbacks, he said. But Seattle's land-use code allows decks, balconies and rooftops to count as open space.

That's not a new change, Podowski said. Balconies and decks have been recognized as "open space" since the 1950s, he said.

The proposed changes to the multifamily code also would reduce requirements for what architects call "modulation" - alcoves, nooks and other architectural ornamentation used to create visual interest in an exterior wall. Ogden is concerned that will mean bleak, featureless walls on future developments.

Podowski said the city's current design regulations are "very prescriptive" and not flexible enough.

"They are not written in an architecturally mindful way," Podowski said.

The city hopes to give architects more flexibility in designing multifamily housing developments, he said.

Another concern of Ogden's is the city wants fewer building proposals to go before the neighborhood Design Review Boards scattered around Seattle.

Design review boards came into being when the Comprehensive Plan was adopted. The boards are made up of architects, designers and urban planners who live in the affected community. Board members offer advice and suggestions about design and how to make it gel with the architecture of the surrounding area. The West Seattle Design Review Board comments on all of the biggest developments planned for West Seattle.

"Buildings that go through design review end up designed better," Podowski said. "But the process increases cost."

The city plans to write into the permitting process some of the changes frequently suggested by design review boards, Podowski said. Design Review Boards would still review the largest projects.

The Department of Planning and Development is scheduled to present its recommended changes for multifamily zoning later this year.

Tim St. Clair can be contacted at tstclair@robinsonnews.com or 932-0300.