Switching from metal to FabricAir ducts increased yields by over 14%

Challenge

The initial five 2300 sqft flower rooms at the facility were originally designed with a different use case in mind, which included a 2-tier racking system. Supply air from the HVAC system was to be dumped at the front of the room and High Airflow Fans (HAF) were meant to distribute the air with laminar flow to the returns at the opposite end.

During permitting and construction, market conditions in Massachusetts changed and the cultivation design was updated to a single-tier set-up. However, because the HVAC was already installed in the first flower room, Native Sun Cannabis proceeded with the existing air distribution design. The results were far from ideal. Cultivators constantly battled humidity and temperature gradients across the space, due to the poor air distribution. The front of the room, near the supply, was much cooler and dryer than the back, near the return, where the air was considerably more humid and warmer. The plants on the front benches near the supply were consistently battered by the HVAC supply air and fans, and needed more manual watering than the rest of the room while showing signs of stress.

The air distribution in the other 4 rooms was redesigned to incorporate a large single duct sox duct running down the center of the 33’x70’ room. While this was slightly better than the previous approach, it was not a success. The single duct did not ensure adequate mixing in the room, which created microclimates throughout the space, which are a detriment to plant health and a microbial risk. This forced the growers to run the space at “safe” VPD setpoints, rather than ideal conditions, thus sacrificing yield to provide antimicrobial protection. This large duct also took up too much headroom, forcing the growers to use multi-bar LED fixtures suited for racking, rather than high-output, high-bay, LED fixtures, better suited for the single tier set-up.

Solution

FabricAir began working with Native Sun Cannabis in 2023 on a comprehensive redesign of the air distribution in the grow rooms. FabricAir engineers worked alongside Director of Cultivation Cody Gagliardi to create a repeatable approach for all flower rooms to eliminate microclimates and microbial risks in the spaces while making room for lighting upgrades, better suited for single tier grow rooms.

The FabricAir design approach was described by Mr. Gagliardi:
“FabricAir worked closely with our team to satisfy all the needs in each space. Several designs renditions were provided based on our requests. All designs were thoughtfully and quickly turned around for review. Pricing and delivery times were the best-around when put up against competitors in the market”.

FabricAir created custom duct solutions based on the constraints of each room to optimize air flow in the spaces for the re-design. HVAC unit size, supply CFM, and existing duct supply attachment points were considered in each room to ensure the installation was straightforward and efficient. The optimized air distribution plan utilized 4 evenly spaced, parallel FabricAir ducts running the length of the room. The air dispersion from each duct was designed to provide conditioned air to every table, at precise uniform velocity, strong enough to penetrate the canopy without causing unnecessary stress on the plants. FabricAir provided detailed plans for the fabric ducts and suspension systems, allowing for a seamless integration with the facility’s existing HVAC infrastructure. A local HVAC company was employed to retrofit the existing ducting and install and affix the fabric ducts. The lightweight material and modular design facilitated quick assembly and installation in the rooms minimizing down time in the space. The entire retrofit installation for Flower room 1 only required 5 business days. FabricAir has since been installed in 2 more flower rooms with similar timeframes for installation, and more retrofits are planned for the future.

Results

The implementation of FabricAir ducts at Native Sun Cannabis yielded significant positive results, enabled by better environmental control. Utilizing the FabricAir systems, Native Sun Cannabis rooms are now running more efficiently than before while also eliminating the microclimates in the space. The multi-duct distribution strategy, coupled with the porous fabric and linear dispersion substantially increases air mixing and uniformity throughout the space. This improved distribution allows for tighter environmental control set points and the company has achieved approximately 10°F lower setpoints at the same RH% (Relative Humidity) with no equipment changes to the HVAC or dehumidification circuits. This precise control allows for more effective crop steering and maintains ideal environmental targets for optimal growth.

Mr. Gagliardi states:
“These results created a greater output of biomass while reducing the microbial risk in space. Plants are noticeably happier and can be pushed harder with more feed and water, resulting in a substantial increase in yield, aroma, and potency in these rooms compared to the previous scenarios before retrofitting with the FabricAir duct system.”

Summary of results – Retrofitted Flower rooms vs previous design.
– Overall dried flower yield: 14.0% increase
– Average TAC (Total Active Cannabinoids): 13.2% increase
– Average Terpene Percentage: 54% increase
– Pass Rate percentage: 99.65%