By Marc Stiles, Puget Sound Business Journal (subscription required)

The size of new houses on Mercer Island will be limited more than anywhere else in the region starting Nov. 1, when new restrictions that the city council approved on Tuesday take effect.

The council voted 5-1 to update the city's residential design standards and approved a new rule to protect mature trees.

The code update affects all of the 6,950 single-family lots on the island, which is a choice market for builders of new homes. The island's average household income of $183,200 is the Puget Sound region's second-highest behind Medina, according to Puget Sound Business Journal research.

New construction and remodeling projects can still be vested under the old code until the end of October, city spokesman Ross Freeman said.

After that, new homes won't be able to cover more than 40 percent of a lot, down from 45 percent. Maximum heights have been cut from 35 to 30 feet, and at least 30 percent of large trees must be kept when a lot under goes major construction. The rules also limit the amount of "hardscape" surfaces, such as decks and patios, to 9 percent of a lot.

Residents who pushed for the change raised concerns about how quickly the character of their neighborhoods have been changing, with old houses being replaced by larger ones.

While the city has been working on the update for about a year, critics say the city rolled out the new rules hither and yon, discussing different changes at different times. They were not discussed as a comprehensive package, according to the Master Builders Association of King and Snohomish Counties, which asked council members to slow down the process and consider their recommendations.

"This is a lose-lose. The (homebuilding industry) was not heard and the community's primary concerns were not addressed," David Hoffman, a government affairs staff member for the homebuilders, said after Tuesday's council vote.

People are still going to build big houses that will upset some neighbors, he said.

This week, Shannon is at Sun Mountain Lodge at the MBA Membership Trip, speaking with Nancy Grygorowicz-Davis, director of marketing & events at the MBA, about MBA events.

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Forget your favorite tiny home hunter show for a minute—this is real life. Despite what the media tells us, homeowners and homebuilders, have only very recently begun to shrink their standards in favor of more compact confines.

In the 1990s, if you can remember back that far, about 23.2 percent of homes built were 3,000 square feet or more according to a builderonline.com article based on data taken from the Census Bureau American Housing Survey (AHS). But after the recession, square footage dropped, right? Not so much. The study, which looked at the years between 1990 and 2015, saw the number of 3,000-plus square foot homes built actually increase to 28.6 percent from 2010 to 2015. In fact, the tiny trend didn't really start picking up steam until mid-2016, when millennials and other such first-time buyers became a big enough segment to affect census numbers.

What's interesting is that the minor dent young folks and first-timers are putting in the overall evolution of expanse isn't enough yet to pull builders off course. As labor and land costs expand with our house sizes, builders are less likely to put themselves at risk, opting to operate in the higher-end housing market boasting secure returns, as opposed to taking a less calculated dip into the lower-end income pool and the smaller—dare we say ‘tiny'—household segment.

Does that mean lower-end shoppers are out of luck?

Not necessarily. Townhouse construction is on the rise, accounting for 9 percent of single-family homes from 2010-2015 (up from 6 percent during the ‘90s), and, according to the Builder article, recent data reports show townhouse construction making upwards of 12 percent of total construction in current quarters.

Will townhomes and tiny houses continue to creep into the bigger picture? Time will tell, but it's safe to say as costs continue to rise and people continue coming to hotspots like Seattle and the Puget Sound region, both builders and buyers will continue to push traditional housing boundaries and seek out less expensive, more practical means of housing.

Should be an interesting evolutionary ride.

Craving more on less? Check out Seattle's tiny home revolution.