Are you sure you need a fan this size? I recall that our rooms are similar sizes. For my new room I calculate that I could use a 340 CFM although I'm getting a 440 CFM for good measure and in case I find myself with more space in the future. I base my calculation on a complete air exchange every 5 minutes.

Here is the calculations needed to size the fan:

1. H' x L' x W' / 5 where 5 equals the number of minutes it takes to exhaust all air from the tent.

2. Take that number and add 10% for each foot of duct and carbon scrubber.

3. Take the original number from item 1 and x by 1.5 for each 90 degree duct elbow.

4. Take the original number from item 1 and x by 1.3 to account for the resistance created by the scrubber.

Add up items 1 through 4. Add 15% to account for cooling needs and another 10% for good measure. This number represents the CFM rating of the fan you need to exchange air every 5 minutes.

If you want to calculate for 4 or 3 minutes just adjust the calculation in step 1.

Be sure to get a fan speed controller so you can dial it down.