Types of Coverings
Choosing the right covering for a cannabis greenhouse may be a little more complicated than choosing a traditional greenhouse covering. The key is finding the right balance of light transmission, light diffusion, and light blocking capabilities. In most cases it isn’t a single covering but some combination of coverings that will give you the desired environment.
Light blocking materials are most often used on the endwalls and sidewalls of the greenhouse, and clear materials are then used on the roof and in the gables. This provides a nice combination of light transmission from above and a certain level of privacy and security below.
Clear, light transmitting coverings include:
- Multiwall polycarbonate
- Diffused corrugated polycarbonate
- Clear poly film
Available light blocking materials include:
- White/Black/White multi-layer polycarbonate
- Painted sheet metal (usually insulated)
- Black/White poly film
High light transmission is the highest priority but light diffusion percentage, anti-condensation properties, and insulation value also anti-condensation properties, and insulation value also play a role in deciding the right covering for your location. Corrugated polycarbonate generally provides the highest light transmission along with high light diffusion percentages. Multiwall polycarbonate materials are generally a little lower in light transmission but provide more structural strength and rigidity as well as higher insulation value than rigidity as well as higher insulation value than corrugated polycarbonate materials. Painted sheet metal provides the highest level of safety and security on perimeter walls and can be combined with different types of insulation for maximum energy efficiency.
Polyethylene films are by far the most inexpensive covering option. It is available in clear and with available additives that aid in sheeting of condensation and light diffusion and also in a light blocking black/white option of low cost coverage of perimeter walls.