Seattle could ban building big houses with new ordinance

Drastic changes could alter home construction across Seattle.

Seattle City Council is discussing a draft of a new ordinance that would dramatically reduce the size of house you can build on your property.

The new rule would limit square footage based on the size of your land.

It’s tied to policy that will make it easier for people to build backyard cottages, or accessory dwelling units.

“I’m proposing to limit the size of new single family homes,” said Mike O’Brien, Seattle City Council member (District 6).

The ordinance would require new homes to have a Floor Area Ratio (FTA) of 0.5.

It would mean a new home must be no more than half the square footage of your lot.

So on a 5,000 square foot lot, you could build a 2,500 square foot house (not including below ground and backyard cottages).

A 6,000 square foot lot would be limited to a 3,000 square foot home.

“Part of that is to say we don’t need a bigger more expensive housing unit that’s only going to house a couple of people. That doesn’t help our housing crisis,” O’Brien said.

The idea is to encourage people to use their property to build “accessory dwelling units” -- things like backyard cottages or an attached, but separate living space to create more affordable housing.

But Carlisle Classic Homes, a house building and remodeling company, says that policy would seriously limit your ability to build and remodel your home.

“It literally almost reduces the size of the home you can construct or renovate to by one-third,” said Alex Adolfi, principal at Carlisle Classic Homes. “I think this is going to be a challenge for people on these small Seattle lots,” he said.

One house they built in Wallingford house they built is 5,000 square feet on about 6,000 square feet of land. If built after the ordinance, it would need to be 2,000 feet smaller.

For homes on land less 5,000 square feet, the cap on house size is also 2,500 square feet.

But bigger homes are what people want.

“That’s what we get asked for all the time, I need more space, I need more space,” Adolfi said.

The city’s data shows almost half (47 percent) of all the new homes built since 2010 have a bigger floor area ratio than the new proposed 0.5 limit.

“I think you’ll see it drive people out of Seattle, unfortunately. Someone doesn’t want to come in to Queen Anne to spend a million dollars on a home and be capped at 2,500 square feet,” Adolfi said.

O’Brien said that’s OK.

“We are saying yeah, if you want massive houses on smaller lots, maybe Seattle is not the spot for you,” he said.

He said a family could add on one or two accessory dwelling units intended for multiple families.

“Maybe one family is using two units because they want it. You know, we’re not totally preventing that,” he said.

The City Council’s sustainability and transportation committee discussed the proposed ordinance Wednesday.

The size limit on big homes, would exclude those backyard cottages and attached separate dwellings.

“The derogatory term is ‘McMansions.’ These cute little houses get torn down and a big monstrous structure McMansion shows up in the neighborhood. I rarely hear people say that’s good,” O’Brien said.

But one speaker at the meeting Wednesday said he’s had plans for decades to build a home to fit his whole family -- when the time is right. But the size limit would squash those plans.

“When you buy property you look at the zoning you do the research. You see what you can and can’t do, and you hold onto it long term until you can afford to do it. To have that taken away is unfair,” he said.

Carlisle Classic Homes said it makes sense to make it easier for people to build another living space on their properties, but forcing property owners to 
limiting the home size doesn't.

“If you’re going to allow someone to use so much of their lot, they should be able to use that how they want. Whether it’s a single family home or as two individual structures,” Aldolfi said.

The legislation will formally be proposed on June 3 to full council.

A public hearing of the proposal will be Tuesday, June 11 (5:30 p.m. S&T committee).

A vote on the legislation could happen as early as June 18.

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