I have learned a lot here, but this is one thing I still don’t quite grasp. I always thought the more air exchange in a grow area, the better. But some people do intentionally recirculate the grow area’s exhaust back into the grow area. This surprised me when I first seen about it. Then I got to thinking that may be a good way to help heat the 4x4 tent I’m going to get when it needs some heat this winter. Or at least reduce the amount of heat needed from the ceramic heater I’m going to use. I was thinking about tarping off a small area in my basement for the tent. Maybe figure out a way to insulate it better without actually going through the trouble and expense of building an actual room. Then I could heat that small area with the ceramic heater and exhaust the tent directly into the small area I make. I could control the air exchange between the small room and rest of the basement.
I’m White Widow rambling now. Sorry.
So I’m interested in hearing about anyone’s recirculation methods. If you wanna talk about it.
I recirculate my air in the winter to help with heat. I am in a shed and winters get cold. I also have a eclectic baseboard heater to heat the place. My situation is a bit different I have a prep room where the heat is and my air for the grow room gets sucked in from there and then dump back into the prep area. So you could do something similar like you are thinking with panda film heavy duty plastic that is reflective white on one side and black on the other. Maybe a couple 2x4 to help support the plastic but not necessary to build walls. The panda film will be the walls.
Hey just thought I’d chime in with my penny’s worth. My first grow ( not long ago ) was in an attached storage room. For heat I bought a floor/ceiling vent diverter and 20’ of dryer vent hose and some duct tape. I installed the vent hose from the heater vent into the room. I used a dryer vent filter ( It filters any lint or dust from dryer) exchange box and extra vent hose and exhausted that into the room for heat when dryer was activated. At night when temps were 10* the inside temperature of the outside storage room was 82*. When temps warmed up at spring I used the A/C vent just like the heater vent. I installed a small 3” usb fan in upper corner for outside ventilation with a dryer flap so cold air could not freely travel in. It worked really well. I’m inside now and control my grow room temps the same way. 84* day 68* at night it’s what my A/C is set for. I like it cold lol. With the ac piped in even the heat from 3 LED panels and numerous other lights it never gets hotter than 84*. Both areas were 5X8. Don’t know if that’s what kind of help you were looking but I’m green cracking at the moment so I ramble lol
I looked at recirculating the air to keep my girls warm. However, I was concerned about recycling the humidity, which I did not want to do. Being that humidity needs to stay in range as well as the temps, I thought I would go another direction.
I made a small fixture with two medium light bases and put two cfl bulbs in there. I increased the wattage until they generated enough heat for the lights out time (I’m growing autoflower, and the extra light in veg doesn’t appear to create any adverse effects). If you need more heat, you can go up in wattage. You can block the light from the plants if you need to, so it’s still dark, but warmer.
It was also suggested to put a fish tank heater in a 5 gal pail with water. Hope this helped.