Mayor London Breed has appointed a longtime ally and former planning commissioner to head the planning department, an agency charged with shaping San Francisco development as the city’s housing crisis persists.

The appointee, Rich Hillis, is executive director at Fort Mason Center for Arts and Culture and has held several senior positions at the city’s Office of Economic and Workforce Development. He left the Planning Commission in September after seven years to become a candidate to lead the department.

Hillis replaces John Rahaim, who announced his retirement in September after 12 years as the city’s chief planner.

Breed said the Hillis “shares my vision for streamlining the housing approval process and eliminating red tape.”

“Our housing shortage has made living in San Francisco far too expensive, and people are being pushed out,” Breed said in a statement. “Rich recognizes that to address this equity issue, we need more housing in San Francisco for families and people of all income levels.”

Breed’s appointment of Hillis comes as she continues to fight with the Board of Supervisors over how to get more housing built. Breed has sought to streamline the process, but supervisors have pushed back on some of her plans. Last week, she said she’ll try to do an end-run around the board and take the issue directly to the voters through a housing ballot measure.

Hillis will run a department of 240 staff members that over the past dozen years has opened up the city’s eastern neighborhoods to taller buildings and more density, including in the Transbay district, Mission Bay, Rincon Hill, Central SoMa, the Mission, Potrero Hill and Dogpatch. But those efforts often involved long delays and fierce political battles.

Yet very little of the new housing has been built on the west side of the city, where neighborhood groups regularly oppose multifamily buildings.

Overall, the new supply has not kept up with the demand as the city has created new jobs much faster than homes. The lack of new housing has led to skyrocketing prices, forcing San Francisco workers to commute farther and farther from where they live.

Hillis said it will take “both practical and visionary solutions” to tackle the housing shortage. He wants new housing spread out across the city and will work to open up west side single-family neighborhoods to multifamily apartments.

Hillis said he will also work on a strategy to meet Breed’s goal of creating 50,000 new housing units in the next decade, 30% of which would be affordable.

“The growth of the last five years has been unprecedented and really challenged our ability to be a diverse and equitable city,” he said.“It’s not just building 50,000 units, it’s figuring out how to do that in an equitable way.”

He added that he’ll take a proactive approach to finding sites, including meeting with executives from Safeway, which owns multiple stores with large surface parking lots. He compared the Safeway to Whole Foods, which has opened stores below housing developments on Ocean Avenue and Upper Market Street, and has another under construction in Mid-Market.

“There is no reason to have large parking lots with Safeways throughout the city,” he said. “Those are prime sites for new housing.”

On the commission, Hillis was known for a calm, even-handed approach that balanced neighborhood concerns against the city’s need to house the new workers who have flooded San Francisco over the past decade.

As a commissioner, he generally voted with the more development-friendly block of mayoral appointees, but not always. In 2016, concerned about displacement in the Mission District, he sided with activists in backing temporary limits on market-rate projects. As president of the Planning Commission, he also sided with anti-gentrification activists in agreeing to move a contentious community meeting about a development at the 16th Street BART Station from City Hall to Mission High School.

Alicia John-Baptiste, executive director of the urban think tank SPUR, called the appointment “a great choice.”

“Rich has the experience to know how to get things done in the very complex environment, which is San Francisco,” she said. “He is also really deeply committed to San Francisco. He understands just how deep our affordable housing crisis is and is committed to tackling it.”

In a letter to the Planning Commission last year, a group of community organizations urged Breed to appoint a director who would represent low-income and communities of color, which have “traditionally and systematically been hit first and worst by plans, strategies and decisions of City Planners and Departmental policies.”

In a tweet, Supervisor Hillary Ronen called the appointment “a shockingly conservative pick,” adding that “it is disappointing that the mayor choose a new Planning Director that has been a reliable vote for developers on the planning commission and turned a deaf ear to communities fighting to stay in San Francisco.”

Hillis, who lives in the Western Addition, has three children in San Francisco public schools. His mother lives with the family in a granny flat on their property. Hillis has been a big proponent of granny flats or in-law units.

Though running the Planning Department is not a job for the thin-skinned — its director is regularly slammed by critics from across the political spectrum — Hillis said his reason for taking on the job was “pretty simple.”

“I love San Francisco, and I see the challenges we are facing,” he said.

Hillis will start March 9.

J.K. Dineen is a San Francisco Chronicle staff writer. Email: jdineen@sfchronicle.com Twitter: @sfjkdineen