Question regarding ventalation for a first time grower.

Greetings all,

I am looking to build a growcabinet with an exhast fan hooked up to a carbon filter, I live in a twin home so odor is somewhat of a concern. The proposed cabinet will be placed in an upper level bedroom closet with ducting tube running from the cabinet to the ceiling then thru the attic to connect to the bathroom ventilation and exiting via the existing roof exhast (appx 25 ft of tubing).

I initially plan on growing 2-3 plants via soil initially and moving my way to hydro on my second run and increasing my plant count (6-9)

I have a few questions:

1) Is my whole ventilation scheme overkill for the amount of plants I plan to grow? Will a decent carbon filter suffice?

2) How loud are these fans? (4" Vortex or Can fans...should I just go with the cheaper axial fans?)

3) I live in the Northern Midwest US where it can get down to -20 degrees F. What can I do to ensure that my ventalation does not put my growning environment in jepordy? (think the duct tubing in the attic) I've seen backdraft dampeners, but not sure.

I also apologize about not having a diagram of my proposed grow cabinet, but if it is any help....I am looking to do something that will emulate the size and layout of the BC Northern Lights Bloombox.

All help is appreciated, if I am going to do this...I want to do it right the first time.

A couple of things to get you started.

- Use insulated 6" duct ... this will help reduce noise
- For that length of duct I would suggest using 6" ... the twists and turns you make to go that distance and route will greatly reduce your air flow.... this will increase your fan's cfm requirments
- always get a fan bigger (cfm) then you "need", I go at least double with short duct runs ....yours might need 3x, just use a speed controller to run the fan slower then max speed..... this will reduce the fan noise and the fan will also last longer.
- get a carbon filter that has Australian RC-48 activated carbon .... this has much more surface area then cheap carbon pellet filters.
- carbon filters work best when the air moves across the carbon slower ... also Carbon stops working when it is wet.... so keep the humidity down.


hope this helps to start you off with some info to look into

good luck