Seattle's new backyard cottage rule both hailed and hated

Not everyone is sold on Seattle’s decision to allow more options to build backyard cottages.

The City Council voted unanimously Monday to expand rules for so-called mother-in-law or attached dwelling units.

It also limited the size of houses – an effort to rein in so-called McMansions.

Supporters believe the changes will provide more affordable housing throughout the city.

"What we're doing here today is really at its core, a modest change to existing law," said Councilmember Lorena González.

But Sara Weaver, a real estate broker who spoke during public comments before the council vote, said the changes will cause housing prices will go up.

"If you think that investors aren't going to be coming in to pick up these properties, you're sadly wrong," she said.

Some of the key points of the new rules:

• Lots can now have two backyard units on the property.
• They aren't required to have parking.
• The homeowner can rent out the house, plus the additions, without having to live on the property.
• Backyard cottages can now be up to 1,000 square feet and 1 to 2 feet higher.

The council estimates about 2,400 units will be created over the next 10 years. It also believes that fewer existing homes will be torn down because of the new rules.

The changes take effect in January.