If you plan to accurately restore a 10,000-square-foot house built in 1910, it helps to have the original plans on hand.

And if you want to make sure the structural work is done correctly, it doesn’t hurt to have a brother-in-law in the contracting business.

Drs. Kenneth and Naomi Mann have both advantages now that they are restoring their Tudor Revival home on St. Charles Avenue.

The couple will welcome aficionados of historic homes to their renovation in progress Thursday, June 11, when the Preservation Resource Center hosts a Renovators Happy Hour on the site.

Happy Hour participants will have the opportunity to tour the mansion, designed by Edward Sporl for Joseph Vaccaro, a founder with Salvador D’Antoni of the Standard Fruit Co. (which became part of what is now Dole Food Co. in the 1960s).

For the Manns, the project realizes a dream that was 25 years in the making.

“My husband and I had just finished our medical school residencies in 1990 when the last member of the Vaccaro family died and the house became available for the first time,” said Naomi Mann, a pediatric epileptologist. “We told Al (Pratts), the executor of the estate, that we were interested.”

For a couple with two young daughters under the age of 5 and careers that had yet to begin, buying the house may have been imprudent, except for one thing.

“My great-grandfather, Chris Larsen, built the house for Joe Vaccaro, so I had a lifelong connection to it,” Mann explained.

According to Mann, Larsen did a lot of work for the Vaccaro family, not all of it related to construction.

“He would take boats to Central America and bring back Honduran mahogany that was used for the paneling and woodwork in the house,” Mann said.

The couple — then in their early 30s — acquired the massive residence, and soon more members of their extended family joined them.

At one time, the group included Naomi Mann’s parents, Malcolm and Lucille Schulz, as well as her sister, brother-in-law and nephew (Mara and Jack Coiron and their son, George).

“I grew up in a multigenerational household, and it seemed perfectly normal to us,” Mann said.

After raising children and getting them launched, the Manns were ready to give the grande dame a face-lift, but fate had other ideas.

“First, there was Hurricane Katrina. A tornado blew through, and both chimneys imploded. Windows broke, flat roofs leaked … it was a mess,” she said. “After dealing with the insurance company for a few years, the national recession hit, but we finally closed on our financing in 2014.”

Luckily, the Southeastern Architectural Archive at Tulane University had copies of the original plans by Sporl, a leading early 20th century architect whose work includes homes and businesses of prominent New Orleanians.

“The drawings are invaluable in helping us restore windows and other features that were either hidden or altered over the years,” said brother-in-law Coiron, whose company, George A. Coiron III, is the historic restoration consultant on the project. C&G Construction is providing additional services.

“We’re doing things like replacing jalousie windows, installed in the ’50s, with new sash that replicate the originals exactly.”

Now, more than a year into the work, progress has not been as swift as either the Manns or Coiron would have liked, due largely to termite damage.

“Structurally, we’re working from bottom to top, replacing or repairing termite-damaged wood so the house will be sturdy,” Coiron said.

When it’s complete, the burled walnut doors and Honduran mahogany paneling will gleam, the formal dining room — with its leaded glass windows — will host grand dinner parties and the music room will be home to a grand piano that Mann recently inherited.

“One daughter is in musical theater, and the other is a songwriter,” said Mann, who is looking forward to having a room devoted to music. “It’s a long tradition in my family: My dad was bandleader for Malcolm Schulz and the Bluebird Melodians.”