The Hammack crew begins to lower a rooftop unit onto the medical clinic. From left are Chad Liller, Jim Kuhs, Mark Jackson of Lennox IAQ Team, and owner James Hammack.
DALLAS, TX — When a clinic for allergy and chronic illness opened up in the Dallas suburb of Richardson, its director wanted the cleanest indoor environment for his chemically sensitive patients. He turned to local hvac contractor Hammack Service Co.

Dr. Alfred Johnson, director of Johnson Medical Associates, was looking for a filtration system that would provide a clean indoor environment free of chemical odors, fumes, mold, and pollen. The system would also have to provide temperature and humidity control for the office.

Hammack, a local family-owned residential contractor with nine employees, was up for the task. Jim Kuhs, service manager, called on the experience of the Lennox Indoor Comfort & Air Quality Team, whose research and development (R&D) lab is in nearby Carrolton.

Kuhs said this job provided a good start for what he hopes will be a fledgling IAQ business.

“We do a lot of the traditional whole-house testing and we work with allergists and allergy relief stores,” he said. “We are in the formative stages of an IAQ program.”

The company includes IAQ strategies during sales presentations and advertises its “blower door test,” in which homes are pressure tested using a large fan hooked up to the front door and a computer to calculate air leakage.

“Using this method, we can isolate the ductwork and show homeowners how much leakage there is,” Kuhs explained.

Hammack often depends on referrals from allergists who know what type of IAQ testing the contractor does. Kuhs said he believes that it may become a medical necessity to improve IAQ.

The job

The task of securing the best possible IAQ for Johnson Medical Associates began with the installation of four 5-ton humidity-control rooftop units, vital to controlling the growth of mold. Each unit was designed to provide multiple comfort zones to allow separate control for each section of the clinic.

Outdoor air to the clinic is filtered through HEPA filters and treated with UVC light, which provides for clean, ventilated air in accordance with ASHRAE ventilation requirements. Other steps were taken to eliminate and monitor pollutants.

“The floors are tiled and the ceilings are low,” said Kuhs. “We used washed sheet metal and sealed the ducts with environmentally safe mastic. We also foil-faced the inside of the rooftop units.”

Water-based paints were used to eliminate the off-gassing of chemicals found in standard, oil-based paints. HEPA vacuum cleaners were used to clean the building and sealed lights were used to prevent air leakage through light fixtures.

As a final measure, the office was put under positive pressure to minimize the leakage of dirty air into it.

“This was an atypical job for us,” said Kuhs. “But we designed it for better-than-cleanroom standards. We can use this same technology for residences, and for gas or heat pump systems.”

How to market your IAQ ideas

Besides taking out an ad touting a blower door test, Kuhs said there are other ways to stir up interest in an IAQ business.

“You can approach allergy-relief stores and give them ideas about the type of work you do,” he said. “You can also contact local allergists and talk about your business.

“You should have a very good idea of what you are doing. If you don’t, you could make the job worse.”

Kuhs said that sealing ductwork properly is very important, and it is also part of basic hvac knowledge — or should be.

Sidebar: A family affair

Hammack Service Co. service manager Jim Kuhs credits the commitment to customer service and Hammack’s family atmosphere for the contracting company’s success.

James and Patsy Hammack have owned the residential and light commercial service business since 1972. Daughter Rae Nan runs the office.

“It means something to have a family-owned business,” Kuhs said. “Consolidation has worked to our benefit. Dissatisfied customers [of consolidators] have come to us because they prefer to deal with a family-owned business.

“Our biggest loss of customers is through the obituary column.”