By Nico Escondido

Many growers—even those with more experience and expertise—can make the fatal mistake of rushing into a cannabis grow op. The most important consideration when starting up a room, whether it’s a closet, bedroom or warehouse, is how you will construct the space surrounding your garden. Building your room is more important than the system you use, the method of growing you choose or the strains you grow out, because without complete control of your growroom, there’s no guarantee of a successful harvest.

Designing your space is an integral part of creating an indoor growroom. A good place to start your planning is at the top and bottom of your room. Airflow and circulation are essential considerations for the design of your growroom, as everything from temperature to humidity to plant respiration depends on your exhaust and intake systems.

To begin, start by plotting out where your system will stand; usually this is in the center of the room, but depending on the doors or windows, it can vary. Then mark the floor with tape to get a visual on your layout. Next, think about light placement over your garden. This is particularly important for your room design if you plan to air-cool your lighting set-up.

Air-cooling your lights is a great way to control the atmosphere and temperature. But be forewarned: Using an advanced strategy like this can create twice as much work in terms of building your room. Because using an air-cooled lighting system requires an exhaust/intake system that is separate from your general room-exhaust/intake system (used for ventilation and air circulation), this means twice as many fans, holes and ductwork.

The bonus here, however, is that with a separate cooling system for your lights, you can safely use a CO2 system in your garden without worrying that the gas will get sucked out when your room exhausts. Because you’re air-cooling your lights, your room’s fans should vent the air much less frequently, since garden temperatures will be lower.

Recirculating the air in your garden serves multiple purposes. Besides blowing fresh air (with more CO2) past your leaves, growroom intake and exhaust fans help keep humidity down and prevent heat pockets from building up over your garden. Heat build-up is big problem in poorly ventilated growrooms.

When all of this is taken into consideration, a simple conclusion is that every growroom should have an intake fan low in the room to bring in cool air and an exhaust fan near the ceiling to expel hot air. Some growers may even use ducting to extend the fan’s range or to exhaust a specific area, such as directly above the lamps. Keep in mind that in larger spaces, ducting from lights, vents and fans will need to be suspended throughout the area, and this is no easy endeavor.

Also remember that if you decide to utilize an air-cooled light, you will need to find two additional points—one to intake cooler air to run over the bulb, and one to exhaust the lamp’s heat. However, depending on your room’s size, it may not be necessary to use outside air to cool your bulb. In some smaller set-ups, it can be efficient enough to simply suck hot air right off your lamp by attaching some ducting to a flange on the hood of your light and a fan at the other end. For beginners, this can be a great technique to use, since it would allow the same fan to serve as your growroom’s overall exhaust fan. In a smaller room, this simple system could keep temps low enough to effectively kill two birds with one fan.