No doubt, the comfort amenities have helped make it one of the area's hottest spots for wedding receptions and other social functions, year-round.

Tim Kaiser sweats a connection during final installation of the 500 MBH, sealed-combustion Laars Pennant system.

Project Overview

The 3,000-square-foot pavilion is constructed around a slab foundation. The classy, glass-enclosed area is 1,800 square feet in size, and the slab underneath that area is radiantly heated, supplemented by hydro-air. Fox Mechanical chose 1/2-inch RadiantPEX tubing supplied by Watts Radiant through Columbus- and Dayton-based Steffens-Shultz, a central Ohio hydronics manufacturer's rep firm.

Eight 300-foot tubing loops provide heat for the fully insulated slab. They used perimeter-banding for the first 10 rows of tubing on each side of the large, open room, placing the tubing at 6 inches on center for maximum heat output below the largest, windowed walls. The rest of the tubing, throughout the center area of the slab, was placed at 12 inches on center.

"At 0 degrees design temperature, we knew we would need 40 Btu per square foot in the large room surrounded by glass," explained Tim Kaiser, Fox field superintendent.

They also chose to install a small HydroControl panel fabricated by Watts Radiant to handle thermostatic mixing, controls, and fluid flow to the in-floor system.

"We put the control panel and radiant manifolds in a small room adjacent to the public part of the pavilion," said Kaiser. "There simply wasn't room for it in the mechanical room for them."

The attic mechanical room was truly a tight fit. So tight, in fact, that the mechanical equipment and most of the ductwork were in place before the roof trusses could be set.

"Our two key challenges on the job were space and the ability to meet the heat load," said Fox.

"The attic mechanical room trusses have an 8/12 pitch and offer only five-and-a-half feet of clearance to the peak, is no more than 12 feet wide, and the angled walls are sharp. So, it's pretty much like a crawl space. But, with the pre-planning that we did, we were able to accommodate the boiler, two air handlers, the 40 inch by 20 inch supply and return ductwork, and all the necessary pumps up there. The air handlers are 6,300 cfm and 850 cfm in size. It's tight, but it came together nicely, all things considered."

It was also a space consideration - the architect's desire to keep the maximum amount of ceiling height in the decorative lobby area - that led Dynamix Engineering, the project engineering firm, to propose contemporary, exposed ductwork. "Planners liked the idea," said Fox. "So we ran heavy spiral ducts and painted them, the exposed trusses and ceiling in flat black. It's got a lot of class."

The glassed-in area is essentially a non-insulated, 30-foot by 60-foot sunroom, on a slab, with a 20-foot ceiling and exposed on all sides.

To handle the heat load, Fox installed a 500 MBH Pennant boiler by Laars. "We chose it for its small size, low weight, and very good combustion efficiency," said Fox. "The low-mass, copper-fin boiler is perfect for an application like this."

The 85 percent AFUE Pennant has a fan-assisted, sealed-combustion design. "Rather than maintaining high mass, standby energy at considerable cost, this little boiler meets the need easily and quickly injects incremental energy into system loops on demand," he said.

"What's so satisfying to me about this job is that our work and attention to detail came together in a place that will be enjoyed by so many people in the community," said Fox. "Over the years, this place will become one of the area's most desirable spots for wedding receptions, social events, and other special occasions. And even in the winter, when other buildings like this might be closed down, this pavilion will ready, warm, and comfortable."

Publication date: 07/25/2005