Monolithic Dome Home (Clyde, NC)


Faced with the task of heating and cooling a 5,300-square-foot monolithic dome home, GLC Services had numerous challenges to consider. The home has an open floor plan and no attic through which traditional ductwork could be routed. Because the home is concrete, sound echoes throughout all the rooms, so a traditional forced air HVAC system would be too loud. This issue became even more prominent when the home was purchased by a new owner who hosts a syndicated radio program from the home.

Guy Cox of GLC Services designed the HVAC system when the home was originally built, winning a 2003 Quality Home Comfort Award from Contracting Business, and also completed the retrofit in 2008. He selected Unico as a solution in both cases.


In the original construction, GLC installed a radiant floor system driven by a 4-ton water-to-water geothermal heat pump for heating and a 4-ton Unico air handler for cooling. Unico’s 2-inch ducts were a perfect fit for the home because they could be installed in the small, curving chases where the dome and floor came together and in a small window seat-style chase. To combat noise concerns, the home uses more outlets than normal, and they are positioned to follow the curvature of the walls. The temperature was controlled two different ways. For cooling, the home used one non-programmable thermostat. For heating, there were six heating-only thermostats – one for each zone – along with a Dos Logic controller that enabled the house to operate during off-peak time and receive a special low electrical rate.

The house was sold in 2006, and the new owners had a different lifestyle. The requested the removal of the Dos Logic controller because they would be working on the radio program late at night. They further wanted the home to operate on forced air and radiant heat at the same time, with a cooler indoor temperature in the summer to combat the additional heat generated by the radio show. To solve the problem, GLC installed a 5-ton UniChiller by Unico, which increased the existing systems’ capacity because it was installed in parallel with the geothermal system, only providing the extra BTUs as required. The UniChiller provides hot water for heating and cold water for cooling while being much quieter than a traditional HVAC system. The 4-ton Unico blower module was changed out for a 5-ton variable speed blower module with an advanced control board. A SuperStor 50-gallon water storage tank was selected because it provided the correct size buffer tank as well as an internal heat exchanger, which keeps the propylene glycol lower and prevents it from mixing with the indoor hydronic system. The end result is a system that meets the owners’ needs for noise control, ease of use and temperature comfort.


GLC has twice customized this home to meet the specific needs of its owners, and Unico has provided an ideal solution in both installations. The award-winning monolithic home has been featured on HGTV in a number of shows and in several magazines. Though more than just the homeowners appreciate the quirkiness of the home, they are the only ones enjoying the superior indoor comfort provided by Unico. With The Unico System installed, the home achieves the modern convenience of heating and cooling with the peace and quiet the owners escaped to the mountains to find.