Cannabis operations can take years to perfect their HVAC. But for Brandon Schmitzer of High Mountain LLC in Vassar, Michigan, the HVAC side was a cinch.

Schmitzer and co-founder Allen Franks opened the 8,500-square-foot medical marijuana grow-op in 2020. Schmitzer was an EPA-certified HVAC technician before opening High Mountain Cannabis. He also had growing experience during a 10-year patient/caregiver career under the Michigan Medical Marijuana Program.

The HVAC design features more than 700 linear feet of 16-inch-diameter fabric ductwork by FabricAir for three 1,581-square-foot flower rooms and a small nursery. One advantage of fabric duct is uniform airflow. Plus, fabric isn’t prone to condensation, which could potentially drip into the soil below and possibly affect Michigan state inspections.

There’s also a fabric dispersion plenum for the dry/cure room. The plenum supplies uniform, highly filtered air from end to end of the 47 x 13-foot dry/cure room to prevent mold, mildew, and static air pockets. Schmitzer’s supply plenum, inspired by “air showers” that blow coal dust off miners, consists of two 12-inch-wide cavities created by a 104-square-foot fabric wall.

In conjunction with a return air plenum wall, the design provides uniform airflow throughout the room despite its extreme density of drying plants. The fabric also sports a silk-screened High Mountain Cannabis Company logo.

Mechanical equipment consists of six Goodman 5-ton split systems per flowering room, nine grow-optimized A210V1 dehumidifiers by Anden, six more dehumidifiers in the dry/cure room, and several Anden AS35FP steam humidifiers with a 34.6-gallon/day capacity. The systems’ 2,000-cfm, ceiling-mounted air handlers have electric heat strips. This decentralized strategy adds redundancy so plant quality won’t suffer if one or two units are temporarily offline.

The proof that HVAC design can positively affect cannabis profits is in High Mountain’s impressive harvest statistics of high THC content and nearly three-pound/1,000-watt light — an impressive output when compared to growing meccas like California and Colorado.