Grow Room 101 - Ventilation

[ChanChan203]

So this weeks topic will cover grow room ventilation systems and everyday there will be a new topic pertaining to ventilation systems with some form of information and questions. Remember that every reader is strongly encouraged to post pics and comment threads are for new growers to learn and older ones to share experiences.

So is your grows ventilation up to the standard or are you depriving your plants of their much needed CO2?Ventilation is a major part of any grow it is not near as noticeable at early stages when plants don't breath as much. As plants get bigger their air needs increase and you could be suffocating your plants and not even know it!So what is the proper rule for a ventilation system in a grow room? The rule of thumb is that air should be exchanged in your grow room every 3 minutes but every minute is best! So you may be saying to yourself how do I figure out if my grow room is moving full room of fresh air every 3 minutes it's easy! Take the length width and height of your grow room say your growing in small closet (L)3x (W)3x (H)8 =72 cubic feet. So to exchange air every 3 minutes we would take a third of 72 by multiplying 72x.33=23.76 so say 24 cubic feet a minute or (CFM). Now if you are running carbon filter or any other kind of air scrubber you should equate at least a 25 percent drop in performance for air being drawn through more slowly through the filter. So you would take your total CFM and multiply it by 1.25 so 24x1.25= 30cfm so our total fan requirements for our closet grow would be a 30cfm fan.
Try yourself:
Length x width x height= total grow pace
Total grow space / 3= cubic foot requirement
(optional) cubic foot requirement x 1.25 cubic foot requirement with filter

Questions or comments post below and I would love to see pics of your ventilation set ups and know is your grow room up to the test and as always keep it frosty!

 

[Jimdog]

So this weeks topic will cover grow room ventilation systems and everyday there will be a new topic pertaining to ventilation systems with some form of information and questions. Remember that every reader is strongly encouraged to post pics and comment threads are for new growers to learn and older ones to share experiences.

So is your grows ventilation up to the standard or are you depriving your plants of their much needed CO2?Ventilation is a major part of any grow it is not near as noticeable at early stages when plants don't breath as much. As plants get bigger their air needs increase and you could be suffocating your plants and not even know it!So what is the proper rule for a ventilation system in a grow room? The rule of thumb is that air should be exchanged in your grow room every 3 minutes but every minute is best! So you may be saying to yourself how do I figure out if my grow room is moving full room of fresh air every 3 minutes it's easy! Take the length width and height of your grow room say your growing in small closet (L)3x (W)3x (H)8 =72 cubic feet. So to exchange air every 3 minutes we would take a third of 72 by multiplying 72x.33=23.76 so say 24 cubic feet a minute or (CFM). Now if you are running carbon filter or any other kind of air scrubber you should equate at least a 25 percent drop in performance for air being drawn through more slowly through the filter. So you would take your total CFM and multiply it by 1.25 so 24x1.25= 30cfm so our total fan requirements for our closet grow would be a 30cfm fan.
Try yourself:
Length x width x height= total grow pace
Total grow space / 3= cubic foot requirement
(optional) cubic foot requirement x 1.25 cubic foot requirement with filter

Questions or comments post below and I would love to see pics of your ventilation set ups and know is your grow room up to the test and as always keep it frosty!

First off I just wanna say I'm glad someone is finally doing this there is not enough in depth information about alot of growing aspects on this site. If we can slowly cover them each week we will help alot of people myself included! I've just started a new cupboard grow area and I'm onto ventilation now so this is great information! When I get home I'll measure up, add it all together and see what I get! Photo of the just started cupboard bellow

Jimdogggy

 

[ChanChan203]

First off I just wanna say I'm glad someone is finally doing this there is not enough in depth information about alot of growing aspects on this site. If we can slowly cover them each week we will help alot of people myself included! I've just started a new cupboard grow area and I'm onto ventilation now so this is great information! When I get home I'll measure up, add it all together and see what I get! Photo of the just started cupboard bellow

Jimdogggy

Thanks for the support it means so much!! I thought same thing there not like complete guides to certain aspects of grows on here so I thought these threads would help a lot I'm about to start classes on THC University online cannabis course so as I learn more I'll keep providing information to the new and old threads so stay subscribed.
And also great start to the grow I'd like u to keep posting pics so we can see how it goes! If u have any questions or anything feel free to ask.

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[Jimdog]

Thanks for the support it means so much!! I thought same thing there not like complete guides to certain aspects of grows on here so I thought these threads would help a lot I'm about to start classes on THC University online cannabis course so as I learn more I'll keep providing information to the new and old threads so stay subscribed.
And also great start to the grow I'd like u to keep posting pics so we can see how it goes! If u have any questions or anything feel free to ask.

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No problem my friend more will be done this evening so I'll update then. Maybe within this forum people can give their inputs and help me build up this cupboard!

Jimdogggy

 

[ChanChan203]

For sure whatever u need to work on next week if ur gonna start on another aspect we could make that for that weeks topic if need be

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[Jimdog]

For sure whatever u need to work on next week if ur gonna start on another aspect we could make that for that weeks topic if need be

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That sounds perfect

Jimdogggy

 

[ChanChan203]

Heyy back again today with our next topic of conversation which is passive vs active intake in any type of grow space. But before I begin I'm gonna give shout out to my man Pigeons420 who inspired me to begin these pages this for you man!!!

So what is passive and active air?? Passive air is allowing free flowing air to enter the room through the natural negative pressure that your room has with the exhaust fan going. Active air is forcing air into room with a separate intake fan. Now you question probably is which of theses systems is better? Well neither has been proven to be better than the other one in general it just all depends on cost and way room is set up. The general idea of both of these setup is to all air while keeping a NEGATIVE pressure in your grow this prevents smells from leaking and air existing out other places.

So first we will cover passive air passive uses and exhaust fan and just standard holes to allow fresh air to come into but how much is enough?? In a passsive air system you air intake hole or holes should be at least 3 times size of intake hole when added together and still be filtered I would suggest cutting an air filter used on house ac system at least 2 to 3 layer to prevent insects and other debris from comming into room.

Now onto passive air intake your fan cfm needs to configured as 75 percent of total cfm of the exhaust cfm you figured up in Mondays post to keep that negative pressure where it sure be and should be filtered coming into your room just as your exhaust does out of room.

As always pics comments and discussion is always welcome and always always keep it frosty you guys!!

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[Jimdog]

Heyy back again today with our next topic of conversation which is passive vs active intake in any type of grow space. But before I begin I'm gonna give shout out to my man Pigeons420 who inspired me to begin these pages this for you man!!!

So what is passive and active air?? Passive air is allowing free flowing air to enter the room through the natural negative pressure that your room has with the exhaust fan going. Active air is forcing air into room with a separate intake fan. Now you question probably is which of theses systems is better? Well neither has been proven to be better than the other one in general it just all depends on cost and way room is set up. The general idea of both of these setup is to all air while keeping a NEGATIVE pressure in your grow this prevents smells from leaking and air existing out other places.

So first we will cover passive air passive uses and exhaust fan and just standard holes to allow fresh air to come into but how much is enough?? In a passsive air system you air intake hole or holes should be at least 3 times size of intake hole when added together and still be filtered I would suggest cutting an air filter used on house ac system at least 2 to 3 layer to prevent insects and other debris from comming into room.

Now onto passive air intake your fan cfm needs to configured as 75 percent of total cfm of the exhaust cfm you figured up in Mondays post to keep that negative pressure where it sure be and should be filtered coming into your room just as your exhaust does out of room.

As always pics comments and discussion is always welcome and always always keep it frosty you guys!!

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So say in my cupboard <600long, 400deep, 1800high mm> what sort of fan system would I use? Carbon filter not needed. My theory was a couple of 120mm fans at the bottom sides intake and one 140mm at the top pulling hot air out. Along with a couple shitty usb fans inside to move air from the bottom to the top of the case where it will be exhausted. Any advice or changes?

Jimdogggy

 

[ChanChan203]

So say in my cupboard <600long, 400deep, 1800high mm> what sort of fan system would I use? Carbon filter not needed. My theory was a couple of 120mm fans at the bottom sides intake and one 140mm at the top pulling hot air out. Along with a couple shitty usb fans inside to move air from the bottom to the top of the case where it will be exhausted. Any advice or changes?

Jimdogggy

OK so ur total grow space comes out to 432,000,000 cubic millimeters or 15.25 cubic feet so you could easily meat the the exchange rate of once per minute. In my micro grow I used cool master fans because they were relatively quite and cheap but a 140 mm cool master moves 60.9cfm!! A 80mm cool master even moves 24.2 cfm way more than u need still as to the one out two in concept then you wouldn't have a negative pressure in your grow box you want more air going out than you do comming in just by a little bit so if it was me I would mount a single 80mm fan centered in the top of the box to remove hot air and it would exchange full room air ever about 45 seconds and use a passive air system with about 2 or 3 holes same size as the 80mm fan at the bottom spaced a few inches apart to draw cool fresh air in and up along the plants

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[Jimdog]

OK so ur total grow space comes out to 432,000,000 cubic millimeters or 15.25 cubic feet so you could easily meat the the exchange rate of once per minute. In my micro grow I used cool master fans because they were relatively quite and cheap but a 140 mm cool master moves 60.9cfm!! A 80mm cool master even moves 24.2 cfm way more than u need still as to the one out two in concept then you wouldn't have a negative pressure in your grow box you want more air going out than you do comming in just by a little bit so if it was me I would mount a single 80mm fan centered in the top of the box to remove hot air and it would exchange full room air ever about 45 seconds and use a passive air system with about 2 or 3 holes same size as the 80mm fan at the bottom spaced a few inches apart to draw cool fresh air in and up along the plants

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So no intake fans needed at all just a couple 80mm holes? Wow I'm so glad I asked before doing I could have spent unnecessary cash haha.

Jimdogggy

 

[ChanChan203]

Sorry for being late you guys had to go to ER last night but I'm all good now!!! Today's topic of ventilation will be relatively short one it involves air cooled lights!
There are two aspects to consider when thinking of air cooled light it is PAR rating and 6 or 8 inch air cooled hood size

Using air cooled hoods does lover a light part rating by about 5 to 10 percent but allows you to get your light much closers to the plants balancing the loss out

As far as the 6 and 9 inch air cooled goes that depends alot on size of lights being used and how many you plan on running together but more airflow is always better so I would say 8 inches always!!

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[Jimdog]

Sorry for being late you guys had to go to ER last night but I'm all good now!!! Today's topic of ventilation will be relatively short one it involves air cooled lights!
There are two aspects to consider when thinking of air cooled light it is PAR rating and 6 or 8 inch air cooled hood size

Using air cooled hoods does lover a light part rating by about 5 to 10 percent but allows you to get your light much closers to the plants balancing the loss out

As far as the 6 and 9 inch air cooled goes that depends alot on size of lights being used and how many you plan on running together but more airflow is always better so I would say 8 inches always!!

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Hope you are alright my friend thanks for the tip!

Jimdogggy

 

[SewStoned]

More coming?


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[Mistercpp]

Brain fart...nevermind

 

[ChanChan203]

Yes I'm hoping to restart I had gotten very sick and was in hospital for over a week but I'm out n I w net through all my appoints and they say I'm back to my old self!! If you have any topics you would like to cover just tell me I'd rather cover topics you actually need help with!! Looking forward to beginning again

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[GhostQueries]

Hey a little late showing up, but this thread is saving me some sanity! Appreciate the insight.. one question in calculating my CFM I took the cubic feet and multiplied by 1.25 to account for the filter. Does this also account for insulated ducting and bends in ducting?

Working with about 38 cubic feet. Assumed 4" fan/filter will suffice. Would it be better to go with the 6" fan/filter and dial down? Just looking to get the numbers correct in my head



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[ChanChan203]

Hey a little late showing up, but this thread is saving me some sanity! Appreciate the insight.. one question in calculating my CFM I took the cubic feet and multiplied by 1.25 to account for the filter. Does this also account for insulated ducting and bends in ducting?

Working with about 38 cubic feet. Assumed 4" fan/filter will suffice. Would it be better to go with the 6" fan/filter and dial down? Just looking to get the numbers correct in my head



Sent from my iPhone using 420

Yes the quarter should calculate enough for minimal bending ducting urself really causes no problem as long as you seal the duct work up real tight with aluminum tape bends are what cause most problems cause air kinda backs up in bended areas and me personally for noise and efficient I would probably run a 6 and dial down that what I am doing in my new grow box build also if you have any body has any questions feel free to message me at any time I haven't made any more of these forums in awhile ik because I been taking classes in building grow rooms through online colleges then when I'm finished I will resume these topix

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[Ego11]

Great thread!
Look forward to following along on this one.

Forgive me if I'm jumping the gun in the lessons, if this is coming up I'm happy to wait it out.

Curious people's thoughts on fan pushing through air cooled hoods vs pulling.

I've read conflicting sides and have tested it both ways, only thing I believe to be an upside to pulling is the suction created helps to seal the light, vs pushing expands the seals lowering the air cooled hoods efficiency.

I've read that pulling creates excessive heat in the motor, reducing motor life. That seems believable.

I've update this setup since but it's bed time for the ladies and didn't want to disturb their rest to snap a picture.

 

[ChanChan203]

Great thread!
Look forward to following along on this one.

Forgive me if I'm jumping the gun in the lessons, if this is coming up I'm happy to wait it out.

Curious people's thoughts on fan pushing through air cooled hoods vs pulling.

I've read conflicting sides and have tested it both ways, only thing I believe to be an upside to pulling is the suction created helps to seal the light, vs pushing expands the seals lowering the air cooled hoods efficiency.

I've read that pulling creates excessive heat in the motor, reducing motor life. That seems believable.

I've update this setup since but it's bed time for the ladies and didn't want to disturb their rest to snap a picture.

I preferably and through all I've learned pull air not push for many of the reasons that you stated as well as I see u tap up all your joints which is great! But if u applying positive pressure to that system eventually there gonna blow out and fail also I would like ur input on what next thread should be

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[Ego11]

I have since switched it over to pull air through the light. Seemed to make more sense. Can't say I seen a difference in temperature one way or another.

Setup like this
Filter > light > fan > exhaust

I was unsure about attaching clamps onto the fan as the ports are tapered so I assumed I would have issues, I taped it up real good and it seems to be working out. All other joints are clamped and taped for backup.

You'll probably notice as well that I have reducers installed on the light. Well long story short. This isn't my first light. Mistakes were made and I had to roll with the punches.