Doctors and nurses saw their first patients Wednesday in the new, larger Petaluma Health Center on the city's northeast side.

The clinic on North McDowell Boulevard underwent major reconstruction over the past year, transforming it from an office building to a state-of-the art medical facility, complete with an expanded dental clinic and a new "healthy living" area.

When all phases of renovation are complete, the 53,000-square-foot center will have exam rooms and staff to serve as a "medical home" for 35,000 southern Sonoma County and northern Marin County residents, many of whom have low and moderate incomes.

"This new center will increase our capacity right away to meet the health and wellness needs of our community, to offer new innovative programs and to truly serve as a patient-centered medical home," said Kathie Powell, the center's chief executive.

The expansion is part of a wave of rapid growth taking place among the North Coast's federally qualified health centers, which are poised to play a major role in caring for the newly insured under President Barack Obama's health care overhaul.

The Petaluma Health Center, as well as the West County Health Centers and the Santa Rosa Community Health Centers, benefit from a valuable reimbursement rate for low-income and uninsured Medi-Cal patients.

The non-profit center aims to serve everyone in the community, regardless of their economic status, said Holly Butler, director of community relations. It accepts patients with Medicare, MediCal and traditional health insurance, as well as those who pay for services themselves.

"If President Obama's health care law makes it through the courts...and goes into effect by 2014, we expect a lot more folks to be armed with insurance looking for a medical home," she said. "We want them to know we're an option for them."

The center will grow into a space four times larger than its former facility on Southpoint Boulevard and serve about a quarter more patients.

For the past several days, staff and administration have moved from the former site, settling in at the airy, brick and glass, Energy Star-certified facility.

The new site will have 44 medical exam rooms, nine dental exam rooms and a medical and support staff of about 150 people. That's an increase of 13 medical rooms, six dental suites and 35 employees.

Wednesday was a "soft opening" for the new site. A public grand opening celebration with food, music and children's activities is scheduled for Aug. 12.

Funded primarily by a $8.9 million federal stimulus grant and another $500,000 in federal funds, the center was one of several community health centers in Northern California and one of 85 nationally that won stimulus funds to expand.

Another $5 million came from tax-exempt bonds backed by Cal-Mortgage that were then purchased by United Health Group via its California Health Care Investment.

Part of the "medical home" concept allows patients to see several health-care specialists during a single visit, using the expertise of a team of professionals to encourage patients' participation in their own care.

The expanded Center for Healthy Living will offer a "movement room" for exercise classes, a demonstration kitchen for nutrition classes and space for massage and acupuncture.

The Petaluma Loves Active Youth, or PLAY, program aims to motivate overweight children who are at risk for diabetes to exercise, eat healthy and grow their own vegetables in an on-site garden.

The Petaluma Health Center's hours will be 8 a.m. to 8 p.m. Monday through Thursday, 8 a.m. to 5 p.m. on Friday and 8:30 a.m. to noon on Saturday.

The offices are at 1179 N. McDowell Blvd.