The Bend City Council is scheduled to discuss on Wednesday allowing more duplexes and triplexes in some residential neighborhoods. It could help a little with Bend’s affordable housing problem.

But city staff is right to suggest that the Council should at least talk about the effect of the zoning change on existing neighborhoods.

More duplexes and triplexes have long been identified as one of the housing types that would help with the city’s housing crunch. There’s no guarantee this type of housing would be affordable to low-income residents. Duplexes and triplexes would, though, be a good option between an apartment and a single-family home for some families.

The Council asked city staff to look at significantly cutting the square feet required for duplexes and triplexes. The city could allow duplexes on 6,000-square-foot lots and triplexes on 9,000-square-foot lots. City code “requires an 8,000-square-foot lot for a duplex and a 10,000-square-foot for a triplex” in the city’s standard zone for many residential neighborhoods, a city staff report says. But the code also requires duplexes and triplexes to adhere to density requirements and that means the limitations are 11,934 square feet for a duplex and 17,901 square feet for a triplex.

For some people, any such change in an existing neighborhood may set off alarm bells. People may be worried that their neighbors would suddenly tear down homes and put up duplexes and triplexes all around them. That seems highly unlikely to happen. In any neighborhood with convenants, codes and restrictions, it would almost certainly not be allowed. But some people will still be worried. And it is a reasonable expectation that when people make one of the biggest investments of their lives in a home that the city doesn’t do things to sour it.

Staff pointed out the city could still retain some sort of restriction on the density of duplexes and triplexes. In Mount Vernon, Washington, for instance, the government allows “duplexes where there is no more than one other duplex or multifamily use within 600 feet, and there is at least 100 feet of separation from another duplex or multifamily use.”

Finding ways to make housing more affordable is one of the biggest challenges of the Council. Allowing more flexibility for duplexes and triplexes is a reasonable step. But the Council should at least have staff monitor what happens to neighborhoods after it makes any change.