Whether you are considering building your own cannabis grow facility or are already in the process, there are a few challenges that you will face in designing the cannabis hvac system. These challenges include vapor pressure deficit, ventilation, and fabric ducts versus metal ducts.
Fabric Duct Vs Metal Duct
Whether you are building a new facility or renovating an existing building, the choice between fabric duct vs metal duct is very important. These materials have a huge impact on the environment, occupant health, and cost.
Fabric duct is a lightweight alternative to metal duct. It is less expensive and easier to install, reducing labor by 40-70%. It also prevents condensation on metal ducts, preventing the growth of biological contaminants.
Fabric duct systems are available in different patterns and colors, allowing owners to customize the appearance of their facilities. Fabric duct systems are also engineered to create precise surface permeability, which promotes more uniform airflow.
Fabric duct systems are a great alternative to metal duct for grow houses. Because they are lighter, less expensive to install, and easier to clean, fabric duct is a better option for cannabis cultivation facilities.
Vapor Pressure Deficit
Managing Vapor Pressure Deficit (VPD) is an important aspect of growing cannabis. A plant needs a specific level of VPD in order to maximize its growth. If the VPD is too low, the plant may experience water stress, which can lead to mold and fungus growth, and root rotting. If the VPD is too high, the plant may suffer from reduced root absorption, which can negatively impact its growth rate.
Vapor Pressure Deficit is calculated by subtracting the water vapor pressure of saturated air from the water vapor pressure at a specified temperature. For example, if the air is 90% saturated, it would have a vapor pressure of 2.64 kPa. Increasing the temperature by just a few degrees can increase the saturation point.
A high VPD means a plant will have more transpiration, which is the process by which water and nutrients move through the plant. Transpiration is important for plants because it helps the plant uptake the nutrients it needs.
Challenges in Designing a Cannabis HVAC System
Creating a quality HVAC system for your cannabis grow room isn’t as simple as it sounds. The challenges you will face include temperature control, ventilation, humidity, and odor control. The right HVAC system is critical to your crops’ growth and health.
Maintaining humidity levels of 60% to 70% is essential to plant health. Overly high humidity can result in mold growth and mildew.
Temperature ranges and light ranges are also important factors to consider when creating a suitable grow room environment. Cannabis plants require 16 hours of light per day.
In addition, you’ll need to ensure that your HVAC system is capable of handling the heat from lights. Most HVAC systems are designed for return-air temperatures of less than 40 degrees Fahrenheit. If you have a larger grow room, you’ll need a more powerful HVAC unit.
