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How a flexible “plex” design could add lower-cost homes, green space, and walkable, vibrant neighborhoods—fast—across housing-strapped cities.
As people across Cascadia buckle under soaring home prices and rents, leaders are scrambling to legalize, or try to legalize, more “middle housing” options amid their single-detached-dominated stock. While options like laneway homes and backyard cottages, duplexes and triplexes, may get the job done in some locales, bigger cities will need bigger solutions—and fast.
Vancouver, British Columbia, has perhaps an over-lauded reputation for transit-oriented development, given its mere handful of tall neighborhoods. The city was early to legalize laneway homes in 2009, seen then as an incremental way to add more compact, environmentally friendly housing “without incurring the wrath of. wealthy homeowner groups,” some of whom expressed shock that a person might be able to look from a modest laneway home balcony into the primary home’s garden. About 4,500 laneway homes have been built there since, with another 4,000 planned by 2028. They’re popular, and as of 2018, fully 45 percent of newly constructed houses included a laneway home, and many of them also incorporated attached mother-in-law suites.
Fourteen years later, Vancouver planning staff have now proposed legalizing four and sixplexes across the city, including in areas currently restricted to single-detached houses. The new proposal would allow a modest 16 percent increase in building size across the city’s low-density zones. It would also permit more units: four or six homes would be allowed, depending on the lot size. Right now, only three units are allowed in most detached house areas (the main house, plus an attached in-law suite and a laneway house).
The proposed 16 percent increase in housing density is not enough to make up for decades of inaction. Detached home prices in the once-affordable East Vancouver have increased 100 percent in just the past ten years. Yet nothing but these homes is permitted on 81 percent of Vancouver’s residential land, effectively excluding anyone who can’t afford the high price of a stand-alone house and freezing even a relatively dense city like Vancouver in a predominantly suburban state.
The results aren’t surprising: Vancouver’s population has grown more slowly than that of its surrounding suburbs, with detached home prices ballooning to $3.3 million on the city’s west side, well out of reach for most families.
If we faced a less daunting housing challenge, then this 16 percent increase in allowable density might make sense. But our problems are bigger than that, and our solutions are going to have to be, too. It’s time to end detached-house zoning—and give Vancouverites more ways to call the city home.
INTRODUCING “THE PLEX”
Fourteen years after laneway homes were legalized, the results are in, and prices are way, way up. Whatever we do next, let’s not make the same mistake of doing too little, too late. In the spirit of doing enough, and fast enough, we set out the following goals, looking to bridge the gap between the city’s towers and its single-detached-dominated neighborhoods:
Make it dense—and build up, not out.
Make it affordable.
Make it fast.
Do it everywhere.
Make it accessible.
What would a new housing form that does all of these things look like? We propose: “the Plex,” a modular, repeatable apartment building of six, eight, or ten homes.
The Plex is a place for people to raise families, meet friends, and live their lives on quiet streets in the neighborhoods they love. They combine the large units and yard space that people associate with detached homes, with the walkability and affordability of apartments.
Include a shared rooftop patio and solar panels, plus front and rear balconies to liven the streetscape and allow neighbors to mingle. Ensure full accessibility for residents of all abilities, design to energy-efficient passiv

Early efforts in California, Colorado, and New York offer lessons to get started.
Cascadians are swapping gas furnaces for heat pumps, gas stoves for induction cooktops, and gas dryers for electric ones. The “electrify everything” movement is accelerating, spurred by new federal, state, and local incentives.
But when and how are we going to start pruning the gas system accordingly? Without shutting down gas infrastructure in tandem with electrification, an ever-shrinking number of gas customers will face ever-ratcheting costs to maintain a bloated gas system. Renters and low-income people who face the greatest hurdles to electrify are at the most risk of this so-called “death spiral.”
Thankfully, there is a better way: strategic gas decommissioning paired with neighborhood electrification. In this world, all the buildings in a neighborhood or area electrify, as opposed to today’s scattershot approach. Then, the gas utility shuts off that part of the system, rightsizing its infrastructure to fit the new, smaller number of gas customers.
Cascadia has yet to start decommissioning gas infrastructure or electrifying whole neighborhoods, but early work underway in California, Colorado, and New York offer some insights to get going. At a minimum, leaders in Cascadia who are committed to clean, healthy buildings and an equitable transition off of gas would be smart to:
Clarify or eliminate gas utilities’ “obligation to serve,”
Require gas utilities to propose areas ripe for decommissioning and neighborhood electrification instead of replacing gas pipes,
Incentivize decommissioning and neighborhood electrification while protecting ratepayers, and
Shield gas customers from future stranded gas assets.
Let’s take these steps in turn.
1. CLARIFY OR ELIMINATE GAS UTILITIES’ “OBLIGATION TO SERVE”
All states and provinces of Cascadia (and all 50 US states) require gas utilities to provide service to any customer in their territory who wants it. These “obligation to serve” laws used to make sense. They prevented monopoly utilities from discriminating against customers who were not profitable to serve, like people in low-density areas or those who use only small amounts of gas. And they helped lower gas customers’ bills by spreading fixed infrastructure costs over more households over decades, a model possible for a gas system that exists in perpetuity.
But we no longer live in a world where the gas system can last forever. And electric alternatives abound for every residential need currently met by gas. The obligation to serve—or, at least, regulators’ interpretation of it—is getting in the way of strategic gas decommissioning.
“A single customer can tank a project,”
explained David Sawaya, Senior Manager of Decarbonization Strategies at Pacific Gas & Electric (PG&E), California’s largest utility, at a 2021 webinar organized by the California Energy Commission (CEC). CEC is funding a roughly $2 million, two-year body of research to identify potential pilot sites in northern and southern California for strategic gas decommissioning and neighborhood electrification. Given the obligation to serve, “every single customer has to agree to electrify” for decommissioning at the neighborhood scale to be possible, Sawaya continued. With recent uproar over an imaginary US ban on gas stoves, it’s not hard to conceive of a single gas system hold-out.
Obligation-to-serve laws are nebulous enough that the issue could be resolved through regulation alone, Professor Heather Payne, an expert on regulatory policy at Seton Hall University School of Law, told Sightline. Payne argues that a state’s Public Utility Commission (PUC) could do away with the obligation to serve simply by shrinking gas utilities’ service territory once the PUC identifies an area ripe for strategic decommissioning and neighborhood electrification.
“Regulators gave service territories and they can take them away,”
she emphasized.
Bu

To reduce housing shortages, small doses of cash could get many projects built. A bill introduced in Oregon this year suggests a clever place to find it.
Oregon’s housing catastrophe comes down to this: Alongside every home built in the state since the Great Recession is the ghost of another home that never was.
Cottages that might have slipped into backyards if they’d been able to cover the sewer connection fee. Apartment buildings that might have filled up with nursing assistants and preschool teachers if they’d qualified for a slightly larger loan. Would-be projects across the state that, for one of a thousand reasons, came up a little short on cash and never left the drawing board.
Economists calculate that it’s added up to the country’s fourth-worst housing shortage. When there aren’t enough new homes, bidding wars begin for the old ones. Since 2010, untold thousands of these price battles across Oregon have driven up home prices more than 60 percent.
A grizzled squad of the state’s housing nerds says they have a “big idea” that could help end these bidding wars by bringing these ghost homes to life, especially in smaller cities where low wages and decrepit infrastructure keep much of anything from being built. They calculate that a $300 million investment could produce 12,000 mid-price homes around the state within several years.
That’d be enough to meet several years’ worth of the state’s new production goal for that price category.
Then, like blueberry bushes, the seeds planted would bear fiscal fruit year after year. Even without further funding, a revolving housing loan fund seeded by a one-time state investment would produce thousands more homes over the decades to come, bringing the total public cost to $10,000 per home created.
The catch is that it’d cost money up front. But the concept’s backers say that if Gov. Kotek hopes to come anywhere close to her high-profile goal of nearly doubling housing production, there’s no more cost-efficient way to push up the numbers.
The idea for making more of Oregon’s ghost homes exist was captured this year in House Bill 2980. On Friday, the Portland Business Journal reported that that bill appears dead for this year; its backers aim to keep developing it and introduce it again.
Its concept is simple. The money comes from the future.
HAPPY HOMES AND GHOST HOMES
In a state with too few happy stories about housing, Mieko Frederick’s sidewalk-level apartment in Newberg, Oregon, might be home to one of the happiest.
Sitting at the little wooden table outside the door to Unit 103, a few blocks from downtown, Frederick cheerfully counted the ways she loves her new place, built in 2020.
“The grocery store is there, the library is there,”
said Frederick, 83, gesturing this way and that from the makeshift patio she set up after moving into the three-story building a year-and-a-half ago.
“I can walk and go everywhere.”
Then there are the stories like the one about the 8th Avenue Garden Cottages.
That was the name Dirk Knudsen gave his plan to add eight 250-square-foot freestanding homes to an oversized backyard just southeast of downtown Hillsboro, a booming tech hub north of Newberg. Within three blocks were a hospital, a university campus, a grocery store, and a light rail stop.
“We were looking for students, lower-income people in the service sector, and also seniors looking to move down out of their existing homes,”
Knudsen recalled.
But between construction costs and the $34,000 per new home that Hillsboro charges to finance new roads, pipes, and parks, Knudsen calculated that he couldn’t bring the cottages to market for less than $260,000 each—and he estimated that nobody would be willing to pay that much to live in one. So he pulled the plug. Today, the backyard is still sitting mostly empty, and the eight households that might have lived there are instead competing for housing with everyone else in Hillsboro.
“WE CAN’T SOL

Three ways to curb the sprawl that traps us on a wildfire treadmill.
It’s time to address the elephant in the room: the best and possibly only practical way to protect homes from fire is to stop building so many of them in places that are primed to burn. According to Dr. Jon Keeley, a fire ecologist with the United States Geological Survey,
“People are so fixated on climate change, which is a very real concern, but the bigger driver of accelerating wildfire damage is building houses in the WUI.”
The wildland-urban interface (WUI) is the area where houses are built in or near natural areas—either through urban sprawl or when satellite developments or individual houses spring up in the midst of forest, shrublands, or grasslands.
This concern is urgent. Wildfires are bigger than ever. Many are impossible to fight. Yet people are flocking towards fire-prone lands and populating the wildland-urban interface faster than any other area in the United States. Some developers are building new homes in the very footprint of recent wildfires. It’s worth emphasizing the obvious: without costly firefighting, these homes will burn down.
These houses trap us on a wildfire treadmill by impeding efforts to restore wildlands to health through “beneficial fire.” They also ensure the diversion of billions of tax dollars to an expanding arsenal of bulldozers, aircraft, and firefighters.
We can’t stop population growth. Cascadia is and will likely remain a major receiving zone for people who appreciate its natural wonders and for climate migrants. What we can do is guide this growth away from fire danger.
According to Tim Trohimovich, Director of Planning and Law at the growth management advocacy nonprofit Futurewise:
“There’s no doubt that the cities and towns and their environs where it makes sense to grow are big enough to accommodate all of the population increase in Washington, Oregon, Montana, and Idaho. We don’t need to build on forestland, grasslands, or farmland.”
In a true meritocracy, the 2023 firefighter of the year award would go to city infill because new construction within existing urban areas is the most effective way to lower our collective fire risk. Runner-up would be compact development contiguous with existing city limits. If past fires are any indication, compactness is the single most important protection against wildfire damage.
Fire-hardening communities against inevitable wildfire is important, but preventing development in fire hazard zones is how we solve the wildfire crisis.
FLOCKING TO FIREPLAINS IGNITES FIRES AND FIREFIGHTING COSTS
Between 1990 and 2010, the number of new houses in or near wildlands in the United States grew by 41 percent. Even more surprising, the number of new homes where fires have recently burned grew by over 60 percent.
Just as it has maps of floodplains, the United States maintains maps of wildfire hazard that chart where fires frequently burn. You can think of these areas as “fireplains.” But unlike floodplains, construction in fireplains is not regulated. And fireplains are expanding as the atmosphere warms.
People are moving into fiery rural places primarily for the amenities. This has become possible with improvements in the communication infrastructure, expansion of the service economy, and the ability to work from home. And, of course, free wildland fire suppression. About 15 percent of WUI houses in the West are second homes. Of course, plenty of people are moving to the WUI to afford a home.
WUI growth tends to follow the riskiest patterns: dispersed, detached housing and isolated clusters of houses surrounded by open space. Planners call the latter “leapfrog development” because developers hop over land close to a city or town and instead erect structures farther away, leaving forest, grassland, or shrubland between clusters of buildings.
Constructing residences near forests and other wildlands in fireplains poses four main problems.
More homes—and t

A quarter-million-dollar budget proviso will fund a study to map opportunities beyond oil.
Within Washington state’s newly released 2023 operating budget for the biennium is a nation-leading step toward oil refinery transition planning. Over the next two years, Washington will devote a quarter-million dollars to analyzing the future of the state’s refineries, laying the groundwork for a clean energy transition that supports workers, safeguards communities, and protects the environment.
There are five oil refineries on Puget Sound---in Pierce, Skagit, and Whatcom counties. But as Sightline has highlighted previously, the state lacks a roadmap to protect workers and communities dependent on these facilities as the region shifts off of oil. That’s a risky bet when experts project oil demand will peak and then continuously decline over coming decades and when, from 2019 through 2022 alone, seven oil refineries across the United States shut down operations without warning. These abrupt closures resulted in more than 3,400 layoffs, millions in lost local tax revenue, polluted land without a cleanup plan, and minimal community say over future redevelopment of the sites.
Washington is now embarking on a different, forward-looking path.
The new $250,000 budget proviso tasks the Washington State Department of Commerce with assessing the future of the state’s refineries. Though an initial budget request of $750,000 submitted to the Senate would have allowed for a fuller analysis, this more modest investment is an important first step. The Department of Commerce will contract with a consulting or research firm to implement the project.
Thanks to this investment, Washington and its refinery communities will gain important information they’ve been lacking to prompt future planning and to guide a thoughtful, inclusive process, including:
1: A transparent picture of both the feasibility and desirability of refinery conversion to alternative fuels. Oil refineries globally are touting conversion to alternative fuels like “renewable diesel” as the way of the future. Renewable diesel is chemically identical to petroleum diesel but produced from vegetable oil (primarily soybean and corn oil) or animal fats instead of from crude oil. Washington’s BP refinery already produces renewable diesel, and it is a much-discussed option for the other facilities in the state. But several US refineries that recently converted to this fuel laid off most of their workers and cut their tax payments significantly.
Plus, biofuels like renewable diesel are coming under increasing scrutiny for their environmental hazards, including using prime farmland or forests to grow their soy or corn fuel feedstocks. Rather than relying solely on industry assurances, Washington will now gain a clear-eyed assessment of this oil industry proposal and its likely impacts on employment, local taxes, and the environment.
2: An understanding of options for workers and communities currently dependent on refineries. More than 4,400 people---2,000 employees and approximately 2,400 contractors---work in the Washington refineries, many unionized and earning well above area median income. In addition, the local governments that house the refineries currently collect from them more than $24 million in property taxes that pay for critical local community services like schools, fire departments, and libraries.
To the first point, this proviso will fund the inaugural proactive assessment in Washington of refinery workers’ skillsets against alternative local industries, looking for transferability. To the second, it will forecast how local tax revenues may fall with reduced refinery output. With this information, Washington leaders will have a clearer view of needed investments to support refinery workers through the energy transition (see some ideas from a recent report on layoffs at a former Marathon refinery in California). And state and local leaders can use this informati

And to escape, we need more fire, not less.
More low-intensity fires could have prevented the megafires that turned 700,000 acres of forest into a “moonscape” and incinerated more than one billion board feet of timber. That is what the Confederated Tribes of the Colville Reservation claim in their lawsuit against the US government. There is good evidence backing them up.
Even with more flexible policy and some redistribution in funding, federal and state wildfire response still does not follow science-based recommendations to allow wildfires to burn when conditions are low-risk and to use intentional controlled fires to restore forest health and climate resiliency.
Of course, there is no one-size-fits-all solution to our wildfire problem. As William Bagley, a seasoned fire professional and emergency manager for the Klamath Tribes, told me,
“Fire’s not rocket science. It’s a lot more complex.”
Still, it’s clear—especially in seasonally dry inland ecosystems—that forests need more fire, not less.
CASCADIA IS STUCK ON A WILDFIRE TREADMILL
Cascadia, along with the rest of the West, is caught in a vicious circle: the more we suppress fires, the worse they get; and the worse fires get, the more we suppress them. It’s such a ubiquitous pattern, and such an entrenched and difficult problem, that it deserves naming. Let’s call it the wildfire treadmill. (Sightline has illustrated the concept above. A higher-resolution version is available for download)
Wildfires have become larger and more ferocious than previously imaginable, and we are seeing more of the megafires that destroy communities and that no amount of firefighting can contain. As the planet warms, most areas in western North America will experience a doubling or more of their fire risk.
The three culprits that put us on the wildfire treadmill are:
Climate change and the accompanying increase in those hot and dry days with strong winds that spread fire rapidly and make fire extinction very difficult, called “fire weather”;
The buildup of “fuels” in the forest: small trees, shrubs, debris, and dead wood; and
The expansion of the wildland–urban interface (WUI), where houses meet or intermingle with undeveloped wildland vegetation.
Ironically, the accumulation of forest fuels is a direct consequence of state and federal policies that since the 1600s in one Canadian province and the early 1900s nationwide in the United States have mandated the immediate suppression of all wildland ignitions. For decades, indigenous Americans caught using cultural fire were often jailed or worse.
Now we face a daunting predicament: having snuffed out nearly every ignition for over a century, we’ve suppressed ourselves into a corner where even a small and innocuous flame can explode into an uncontrollable megafire. So, we continue to fight nearly every fire.
A FIRE IN TIME SAVES NINE
Small, low-intensity fires now, while unpleasant and dangerous, mean fewer large, high-intensity fires later. It’s when a fire is hot enough to burn the entirety of mature trees, called crowning or torching, that higher-intensity fire can take off. At this point, the fire can spread embers across long distances and can become a “crown fire” that spreads from treetop to treetop.
Historically, smaller and patchier fires frequently swept through Cascadia’s seasonally dry forests, clearing out forest fuels. Indeed, throughout the bioregion, much of this fire was intentionally started by indigenous people who used it to prevent more dangerous fires, stimulate seed germination, recycle nutrients, and create open habitats for the plants and animals they relied on for food and fiber.
These lower-intensity fires travel along the ground, fueled by grasses, fine fuels, and small trees. Fire-adapted species, such as the ponderosa pine, with its thick fire-resistant bark, can survive low- and mixed-intensity fires. And these fires, every 15 to 20 years, make it unlikely for any one ignit