A new affordable housing project broke ground Monday in San Francisco.

The project, which was initially planned as a mixed-income property at 300 De Haro Street in Potrero Hill, will now be 100% affordable housing.

"This is more than just housing," DM Development CEO Mark MacDonald said. "It's about opportunity for the young workers, service professionals and middle-income earners who are vital to our city."

Developers will turn the plot of land into an 11-story building with 425 studio units, including some fully furnished units.

MacDonald said the development will be the largest affordable housing project in the city in more than five years.

"We're not just starting construction. We're building momentum, we're showing what's possible," MacDonald said.

To qualify for a unit, individuals and families must earn between $41,000 to $95,000 annually, which is 30% to 70% of the area's median income.

The developers on Monday credited Senate Bill 35, authored by state Sen. Scott Wiener, for streamlining the approval process.

"It has led to thousands and thousands of new affordable homes in San Francisco getting their permit in a matter of months, not in a matter of years," Wiener said.

The building when completed in a few years is expected to include a fitness center, co-working space, green space and retail space. Project supporters said the development is not just about providing housing but also creating new jobs.

"This project alone will have hundreds of carpenters building it, and that in turn puts hundreds of thousands of good paying jobs and benefits," said Ron Rowlett with the NorCal Carpenters Union.

Work is underway on the project, which is expected to be completed in the summer of 2027.