PORTLAND, Ore. -- The city of Portland estimates 260,000 more people will move here in the next 20 years.

But a new survey of 7,000 Portlanders out this week from the mayor's Residential Infill Project Stakeholder Committee shows many Portlanders aren't very excited about all the new apartments and duplexes going into their neighborhood.

Lack of affordable housing, home demolitions and compatibility of new homes in existing neighborhoods were the top three concerns out of the month-long survey.

Housing experts say if we don't start accepting more density into every neighborhood of the city, rich and poor, we'll end up like Seattle and San Francisco, where you have to be a millionaire just to live close-in.

We asked residents what their biggest concern is about growth.

"My biggest concern is that people who want to live close into the city won't be able to afford it," said Portland native Cicely Thrasher.

Colleen Garrett of Portland said, "I think the biggest problem is going to be affordable housing and giving people a place to live that doesn't overcrowd the city."

The Residential Infill Project is a committee of residents, builders, city planners and low income housing experts. They will use the answers to change rules on demolitions, height and scale requirements for new homes and ideas for more density.

Everett Custom Homes President Vic Remmers is on the committee.

"There are a lot of things the city could do to save some more trees and save more houses, like being more flexible about building around them and flexibility on what you can do with the house," Remmers said.

In Northeast Portland's Cully neighborhood, green builder and committee member Eli Spevak has created a new living option, co-housing. Where just two homes used to sit on 2 acres...now, 16 families own and share duplex and triplex walls, a garden, even chicken coop duties. Spevak owns Orange Splot LLC Projects.

Spevak says the public wants less in-your-face density like the huge apartment towers we've seen going up around the city. He wants more than one mother-in-law apartment, or ADU, allowed per property, and some large homes able to be broken up into small apartments. Right now, rules only allow homes on the historic inventory list to be made into multi-dwellings.

The survey results show many Portlanders like those ideas, just not in their neighborhoods.

"The natural response, I understand it, is to say don't change anything in the neighborhood and prices won't go up," Spevak explains. "But exactly the opposite happens. If a lot of neighborhoods all say we're not taking any more density, then you have nothing getting built and people come in and just bid up the prices higher and higher."

Colleen Garrett of Portland agrees we need to change our perspective.

"I think that's going to be a big thing for people in Portland is realizing you don't have ownership over everytrhing and it's going to grow," she said.

Those builders say land and construction costs are so high now, that it's almost impossible to build affordable housing in the city, or anything less than $350,000. Spevak would like to see the city create a subsidy to build smaller, cheaper homes.

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