In Minnesota, where the youth sports season goes from frigid to humid and everything in between, entrepreneur Chris Guertin has come up with a flexible solution.

His company makes lightweight, modular wall boards that can be moved around. That means a pond-hockey arena can be transformed into a soccer or lacrosse field, yoga studio, or any other enclosure with ease.

"There's nothing to drill into the ground, so this is a product that you can repurpose and reuse," said Chris Guertin, president of Sport Resource Group of Minneapolis and maker of the ProWall plastic panels.

The company has sold systems to park boards, YMCAs, summer camps, schools, private clubs and even the Minnesota Wild and other NHL hockey teams for fan promotions.

Guertin, 41, a Florida native, worked in marketing and communications for the Florida Marlins baseball team in Miami. He came to Minnesota in 1996 to work for Inline Sports, the former Twin Cities-based company that sold Rollerblades and eventually $100,000 outdoor hockey rinks made of wood-and-aluminum skeletons.

Guertin, who had longed for his own business, decided there was a market for a lower-cost, plastic "rink" with interlocking features that would require no tools and have no sharp edges.

In 2006, he and his wife, Maria, 39, mortgaged their house, cashed in their retirement savings and raised more than $300,000 to develop and patent the ProWall product.

The first couple of years were dicey. They included six-figure start-up expenses and a lawsuit by Inline, now owned by a Canadian competitor, which accused Guertin of breaking an employment contract. Guertin said he settled in 2008 after months of litigation. The business has been cash-flow positive since 2009.

"Chris had always wanted his own business," said Maria Guertin, who had worked in medical product sales and now manages the businesses. "When he said, 'This is what I want to do now' … I was pregnant and had toddler twins. It was kind of tough at first. I believed in Chris. We had corporate experience and he wanted to get out of [the corporate world]."

The company's first sale came in August 2007 to a secondary school in Towson, Md.

"They wanted boards that are portable for soccer and lacrosse, but that could be taken down in a few minutes for basketball," Guertin said.

The walls come in a variety of sizes and colors, including $6,000 Gaga pits (an Israeli-invented version of dodge ball that outlaws head shots) to $35,000 hockey rinks that include doors and ­netting that traps pucks shot higher than the 48-inch walls. The couple contracts with a Spring Lake Park company to manufacturer and ship ­ProWall products to customers in several dozen states.

Joe McCarthy, an elementary schoolteacher in Farmington, said physical education classes have been cut for budget reasons at his school, so the Gaga pit he bought with grant money has turned out to be a great investment. At recess, he requires his students, many of whom used to stand around, to walk or jog a half-mile, and then they can play Gaga.

"It improves their behavior, helps cut obesity and they perform better in the classroom," McCarthy said. "I started with 30 kids in the pit with a couple of volleyballs … and the goal is to hit it with your hand and hit another students on the leg. And when you're hit you go out for a minute, until somebody else comes out. It's great for agility and improves cardiovascular endurance."

Guertin and his wife ran the company from their house initially. Now, with four employees, they operate Sport Resource Group from a one-story south Minneapolis office building they bought out of foreclosure in 2011. The small space on Hennepin Avenue and 36th Street is complete with toys and school desks that the Guertin kids use before and after school.

The company sold about 100 wall systems last year, bringing in revenue of about $1 million. Sales could double in 2013, Guertin said.

Frank Hassid, executive director of the Tarrytown, N.Y., Jewish Community Center and a sister summer camp, said he's pleased with the purchase of two Gaga pits. They're durable and safer than the previous wood enclosures for campers, including 35 autistic children who attended the summer camp last year.

"It's physical, safe, a great activity," Hassid said, "and the kids just love it."

Neal St. Anthony • 612-673-7144