Visitors to Door County in recent summers may not have noticed anything different at one of its most popular attractions – Al Johnson’s Swedish Restaurant and the goats that roam its sod roof.
“But those goats are now on solid ground – so to speak — after F.J.A. Christiansen Roofing Co. crews completely replaced the roof in a design intended to copy the existing sod roof at the famous restaurant in Sister Bay — and make it look like nothing was changed,” said Brian Schaut, FJAC senior vice president.
Restaurant owners Rolf and Lars Johnson wanted to retain the original Swedish sod look. The 7,800-square-foot roof at Al Johnson’s did perform well over its 35-plus years. But some leaks couldn’t easily be fixed due to the six inches of sod atop the decking.
While the replacement roof has the simplicity desired by the Johnsons, it also incorporates modern technology and design principles — expertise that F.J.A. Christiansen Roofing has acquired through multiple high-profile green roofing projects in Wisconsin and as part of Tecta America, the most significant commercial roofing and environmental roofing solutions firm in the U.S.
After a thorough planning process, work at the restaurant began in mid-spring with the removal of the existing sod and soil; the soil was then stored on site for re-use once the new roofing system was in place. Existing drainage and waterproofing materials were removed to expose the wood deck for inspection.
A significant amount of deteriorated decking was located and replaced. A quarter-inch deck insulation board was installed and then covered with a 60 mil Sarnafil PVC membrane and flashing system. FJAC and Sika Sarnafil teamed up to create long-term details needed for this project.
Next, 6” x 6” cedar timbers were custom cut, stained and installed along the eaves and gable lines to match the original Swedish design. Corrosion-resistant steel brackets that hold the timbers were custom fabricated and painted at FJAC’s shop. Soil retention bars were then installed horizontally up the slope of the roof, approximately six feet apart to hold the soil and sod in place. The bars are staggered and pitched so water will run freely around each of them. The bars also relieve pressure from the eave timbers.
According to Rolf Johnson, when he was a young boy, the original sod roof slid off the building after his father overwatered it. The bars should prevent such an occurrence in this new system.
New copper gutters were designed, fabricated and installed above the entrance and exit by FJAC sheet metal department. The gutter system is open-ended, allowing water to dissipate out of both ends; that helps prevent ice back-up and eliminates the need for conductor pipes. “Additional copper gutter elements were installed between a shingled roof, and the sod roof said,” Jeff Keller, FJAC sheet metal superintendent.
Another modern element that was installed, but which won’t be seen, is a water retention and drainage mat. The Drain and Retain mat accomplish what used to require several layers. The fabric will hold moisture and, thus, help reduce the need for manual irrigation.
Once those roofing elements were in place, the original soil was put back at a depth of five inches, and new sod placed over that. The grass was given several weeks to set before the goats were allowed on the new roof.
“Tecta America, as the nation’s leading green roof contractor, has a reputation for exceptional quality and service,” said Schaut. “The new roofing system we installed at Al Johnson’s Swedish Restaurant has that quality and workmanship people come to expect from FJAC. Our crews were honored to use their modern-day skills and technology to restore a roof system that is based on ancient methods. We were able to retain the character of the sod roof and the charm of Al Johnson’s Swedish Restaurant while providing a modern long-term dependable roofing system.”
The restaurant remained open during the re-roofing project, which was completed on time.
Rolf Johnson said the family is pleased with the new roof and with the way the project was handled.
“Everyone involved was professional and polite,” Johnson said. “I would recommend FJA Christiansen Roofing Co., Inc. to anyone. They stand behind their work.”
The project was one more in a list of green roofs installed by F.J.A. Christiansen on high profile buildings — a list which includes the Milwaukee School of Engineering, the City of Milwaukee, the Milwaukee Public Library, Rockwell International, Discovery World Museum, the University Club Tower, and the Healing Garden at Aurora St. Luke’s Medical Center.
|Operating Unit:||F.J.A Christiansen Roofing Co., Inc|
|Client||Al Johnson's Swedish Restaurant|
|Project Type:||Roof Replacement|
|Location:||Door County, WI|
|Systems Installed:||Sod Roof|