What size fan do i need for my grow room?

Hello,

Can some tell me the equation i need to do to figure out what rating of fan i need to exchange the air in my grow room every 5 minutes. I'm sure there is a simple answer, but I just can't figure it out.

Room 1 - 1.14 m3 (meter cubed)
Room 2 - 2.50 m3

Thanks

P.S Apologies if this has already been asked, but I couldn't find anything on it when i used the search option.

Well, CFM's refers to cubic feet per minute. So convert your dimensions to feet, then multiply the Width x Height x Depth, Divide the number by five, and that's your min cfm you need from a fan.

An example : 8'x8'x8' is 512 cubic feet, divide by 5 (for 5 minutes) = 105 . So for a room that size, you want a fan that moves at least 105 cfm and its always better to have more. The fan I have moves way more air than I need, but I have to run it on high to help keep my temps down.

Cheers for that - I work it out that my rooms will be of the following volumes;

88.26 cf / 5 = 17.65 cfm (min required)
40.32 cf / 5 = 8.06 cfm (min required)

Lol, at that rate i could probably get away with a few computer fans. I here what your saying about having a fan pulling more than what you need to keep temps down, i will prob have to do the same.

Thanks