Former President Jimmy Carter was set to attend a home-building event with Habitat for Humanity in Nashville in 2019 when he fell and hit his head at home in Georgia. He emerged from the hospital with a black eye and 14 stitches, but he refused to cancel his plans.

“I got a message from him saying, ‘I’m fine, I’m coming,’” said Jonathan Reckford, Habitat for Humanity’s chief executive. “It just fit with him so well. He came out and built every day.”

The sight of Mr. Carter, then 95, bandaged but undaunted, and his wife, Rosalynn, helping to screw together front porches that October underscored their importance as Habitat’s longtime public faces. As the group’s volunteers in chief, they deployed the prestige of the presidency to transform a small Georgia housing charity into a global builder with a $360 million annual budget.

Habitat says it has built or improved homes for roughly 62 million people. Mr. Carter, who died on Sunday, and Mrs. Carter, who died in November 2023, personally helped build or remodel 4,447 homes in 14 countries. Mr. Carter gave signed Bibles to families at the end of a home build.

Mr. Carter’s work swinging hammers and hanging drywall with the hopes of expanding homeownership and providing more affordable housing coincided with a dramatic increase in home prices. Now, that affordability crisis has left record numbers of people across the United States homeless and many struggling to afford rent or attain homeownership.

“It’s gotten worse,” said Don Kao, 73, who still lives in the one-bedroom apartment on East Sixth Street in Manhattan that Mr. Carter and Habitat helped to renovate in 1984, when the red brick building was a burned-out shell with no roof.