Developers would be required to reduce the scale of homes they build in Portland's single-family zones and would be allowed to construct more duplexes, triplexes and other forms of so-called "middle housing" on those lots under a tentative set of city proposals that will be made public this month.

The Bureau of Planning and Sustainability is readying the recommendations based on the input of a committee organized to determine the best way to regulate infill development as Portland grows and faces a housing shortage. The committee Tuesday night met for the last time until October, capping nine months of work.

Portland officials are now looking for public input. The proposals will be available on the city's website by June 15, and residents can attend a series of open houses throughout June and July. The committee will eventually make a recommendation this fall to the Portland City Council, which could approve or modify the new zoning rules.

The committee's work comes at a time when Portland is experiencing a boom in development, rising home values and a surge in population growth. Neighborhoods are feeling angst about a rash of home demolitions, which often make way for expensive, towering homes that many feel are out of sync with surrounding houses.

The committee has worked to develop a series of rules that would prohibit developers from building such large, non-conforming homes but also incentivize them to increase supply, density and affordable units by adding accessory dwelling units, duplexes, triplexes and, in some cases, fourplexes.

In other words, many of the 20-plus committee members arrived at a bargain: Developers will decrease the scale of homes, but the homes are allowed to be more than simply single-family dwellings.

Another of the proposals would make it easier, in certain areas, for developers to reclaim historically narrow lots that lie underneath larger parcels where there is currently only a single home. The developers would be allowed to split the parcels to align with the historic lots and add more homes. The city wouldn't require on-site parking and would prohibit front-loaded garages on such lots.

The committee consists of developers, affordable housing advocates, architects, neighborhood representatives and others.

Portland Commissioner Steve Novick said in an emailed statement that he is looking forward to seeing the proposals.

"I've been a vocal proponent of 'missing middle' housing, and I'm also pleased to hear that the committee is looking at ways to limit the size of new single-family homes," Novick said. "I think that one of the things that bothers people in our neighborhoods the most is when developers knock down a moderate-sized home and replace it with a towering McMansion. That bothers me, too."

Though the committee's report hasn't been finalized, a draft of the report and discussions at Tuesday's meeting suggested the committee has identified two ways forward: a majority of members want to more aggressively increase housing diversity and supply in Portland, and a minority wants to put a greater emphasis on preserving neighborhood character.

Multiple members of the committee on Tuesday emphasized that the "increase housing diversity and supply" group comprised an overwhelming majority of the panel. Many in that camp felt Tuesday that the planning bureau's tentative proposals don't go far enough in encouraging more density and supply.

"It was a really vast majority every time we had a discussion," said Mary Kyle McCurdy, a policy director at 1000 Friends of Oregon who is also helping organize the recently launched Portland for Everyone project.

The agreement on the committee between developers, affordable housing advocates and promoters of sustainability to increase density in single-family zones throughout the city mirrors the Portland for Everyone mission and also reflects the City Club of Portland's recent recommendation on housing affordability. It is similar, too, to a consensus reached by a similar coalition in Seattle last year.

But Rod Merrick, an architect and the co-chairman of the Eastmoreland Neighborhood Association's land-use committee, questioned whether the makeup of the committee was selected to reach a foregone conclusion and said he didn't believe there were clear "majority" and "minority" groups on the panel. He and others noted that members' positions changed depending on the specific proposal being discussed. Merrick said he was for responsible growth.

"The use of the terms 'minority' and 'majority' is entirely inappropriate," he said.

*This story has been updated to include comment from Portland Commissioner Steve Novick.

-- Luke Hammill

lhammill@oregonian.com

503-294-4029

@lucashammill