(Photo courtesy EnergyMax)

Contractors Tadd Johnson and Adam Hegland had just finished building a four-unit townhome in Red Wing and were eagerly awaiting the results of a blower door test.

“We did all the work ourselves and thought we would just perform through the charts,” says Johnson.

Instead, disappointment. The results were fine, but not off the charts like they had hoped. They asked the technician what they did wrong, and he explained they could only achieve so much with conventional building materials.

That day four years ago set off Johnson and Hegland’s search for a better building product, which they believe they’ve found in their EnergyMax insulation panels.

Their invention won the cleantech and renewable energy category last week in the Minnesota Cup competition, an annual entrepreneurship contest.

Johnson says he and Hegland, who have been friends since kindergarten, started down the entrepreneur path after they couldn’t find another practical and affordable product on the market for making homes more airtight.

They looked to other industries to see what they used for insulation and eventually zeroed in on polystyrene. It’s the same material that’s used to make disposable coffee cups, only it’s in a much denser form in their panels.

The 4-by-4-foot panels are attached to the outside of the building’s frame and take the place of fiberglass insulation, plastic vapor barriers and housing wrap. Before it’s covered up with siding, the panels make a structure look a like an enormous Styrofoam cooler.

Polystyrene doesn’t exactly have a good environmental reputation — it’s made from petroleum and doesn’t break down in landfills — but Johnson says EnergyMax panels are designed to minimize waste. Cutouts and other extras can be broken down and used as loose fill in attics.

The panels are installed with screws, making them easy to reclaim.

The cost of the panels is comparable to conventional insulation for walls, says Johnson. For ceilings, there is an added expense, but one they believe most customers will recoup within a year from reduced heating/cooling bills.

“We knew going in that if it wasn’t affordable, it wasn’t going to work,” says Johnson.

Johnson and Hegland have built four houses using EnergyMax panels, which can be manufactured by any polystyrene manufacturer. They’re in talks with national distributors about setting up some test markets in other parts of the country.

In February, they ran a blower door test on one of their houses with EnergyMax panels. This time, they were happy with the result: 308 cubic feet of airflow per minute, about two or three times better than their best results using conventional insulation products.