# Proper way to ventilate a room



## stickbait (Feb 2, 2015)

Hi all im new to site and have read a lot of posts im setting up my first indoor grow room its size is 5x5x6.6 planning on using 1000 watt light with enclosed hood this will be my flower room. veg room is 2.6x5x6.6 and will have a 8 bulb flor. should have made clear this is one room with wall between flower and veg floor walls and ceiling are all insulated can wire as needed need to know right way to heat and ventilate an any other help I can get. have six months before I retire and want to get started. would appreciate any help you can give


----------



## yooper420 (Feb 2, 2015)

Sounds similar to my garden room. Measure`s about 7'x7'x7' inside. Built in back corner of garage, up off floor, insulated on 6 sides. 2 passive intakes at floor level, 8" exhaust fan at ceiling level. Also have 2" squirrel cage type blower to use as exhaust fan during winter months. Have completed 6 grows using this garden room.


----------



## stickbait (Feb 2, 2015)

Was thinking can you hook filter to one side of enclosed light and then hook fan to other side pull air through filter then light and out of room with fresh air coming in from bottom of room.just trying to do it rioht thanks for imput


----------



## The Hemp Goddess (Feb 2, 2015)

I don't quite understand your question?  

Ventilation is one of those things that is kind of individualized and usually has to be kind of set up to the space and climate you have.  But some things are common to every grow space.  You need some kind of decent centrifuge type fan (one you can connect a filter to if you need it.  You also need an oscillation fan to move the air around.  

For the flowering room, I would recommend a 450 cfm fan.  One of the common setups is filter-hood-fan.  You can have ducting in between, but you want to keep it as straight as you can without sags.  One bad sag is like 2 90 degree turns.    Many locate the exhaust remotely from the growroom.  In the winter when it is cold, I use the exhaust air from the vegging space to help heat the flowering space during lights out.  I have a larger bathroom type exhaust fan located in the veg space that blows into the flowering space.  This alleviates the need for an auxiliary heater in the flowering space if it gets too cool.

Are you using 4' T5 fluoros  (54W 5000 lumen tubes)?  The fluoros will not get too hot, so cooling them is generally quite easy...one of the things I love about them.

Put the grow space on its own circuit and make sure that the room is GFI protected.

Where these rooms are located will influence how the ventilation is dealt with.  So, where is your space?


----------



## stickbait (Feb 2, 2015)

ok so if im reading this right hookin filter light and fan together is ok to do thank you for info. In your post you said you use your t5 to help heat your flower room this brings up another question how do you let heat and air circulate from veg to flower without letting light in flower room when it light out this is something I been trying to figer out. thanks for responding to my questions so fast you've been a lot of help now I have to go blow some more snow later


----------



## stickbait (Feb 2, 2015)

forgot to tell you grow room is in 32x40 poll barn and I live in Michigan also have t5 8 bulb in veg with a barn this size can I exhaust in barn and draw fresh air also


----------



## The Hemp Goddess (Feb 2, 2015)

Check out light traps.  You can build some kind of box or use ducting that creates a light trap.  The volume of air from the veg to the flowering room does not have to be high volume so putting some kind of light trap (kind of like a water p-trap) will not hurt.


----------



## sopappy (Feb 14, 2015)

stickbait said:


> Hi all im new to site and have read a lot of posts im setting up my first indoor grow room its size is 5x5x6.6 planning on using 1000 watt light with enclosed hood this will be my flower room. veg room is 2.6x5x6.6 and will have a 8 bulb flor. should have made clear this is one room with wall between flower and veg floor walls and ceiling are all insulated can wire as needed need to know right way to heat and ventilate an any other help I can get. have six months before I retire and want to get started. would appreciate any help you can give



You want to exchange all the air in the room 3 - 4 times an hour. (Edited --> WRONG! THG caught it, 5 - 8 times an hour, sorry) 
You also want a little more air out than in. You'll have to do some math. The fans move Cubic Feet per Minute (CFM). Heat will drive you crazy with the 1k streetlight too, you may want to put it in a tube (unless that is what you meant by enclosed)


----------



## yooper420 (Feb 14, 2015)

stick,
Michigan huh ? Yooper or troll ? Your set up sounds similar to mine, other then I use LED`s. My garden room is in a corner of my garage (30x50) up off the floor. Garage has 3 courses of blocks, with a 8 foot 2x6 wall on top. I exhaust the room into the garage itself, with no problems through 6 grows. Also grow year round. Room is well insulated.

PS,
Garage is 30'x50', room is 7'x7', use 6.5'x3' to grow in.


----------



## The Hemp Goddess (Feb 14, 2015)

sopappy said:


> You want to exchange all the air in the room 3 - 4 times an hour. You also want a little more air out than in. You'll have to do some math. The fans move Cubic Feet per Minute (CFM). Heat will drive you crazy with the 1k streetlight too, you may want to put it in a tube (unless that is what you meant by enclosed)


 
You really need to exchange your air a lot more than several times an hour.  You want to exchange the air in your space at least once every 3 to 4 minutes.  I personally like to exchange mine more often--at least 2-3 times a minute, if possible.

I run a 448 cfm Vortex for a space that is 3 x 6.5 and has a 1000W in it.  I have a large air coolable hood.  The fan is located remotely from the closet and connected with 6" insulated ducting.

Yes, an enclosed hood is an air coolable hood.  I, personally, find cool tubes too small for 1000w lights.  I prefer larger air coolable hoods over cool tubes when you get into bigger wattages.


----------



## sopappy (Feb 14, 2015)

And I promised I wouldn't do that.... my apologies, Stickbait  
Good thing TheHempGoddess is keeping an eye on me, thanks THG. 
I remembered that wrong... evacuate *at least* every 5 - 8 minutes.... 
I should be running my exhaust fan for at least 2 minutes every 10 minutes but I'm poor so I go 2 minutes every 15 and shot off my mouth before thinking...  sheesh, I'm part of the very problem I whine about.


----------



## Batman (Feb 14, 2015)

cares a lot cose ventilate


----------



## stickbait (Feb 16, 2015)

I was thinking around 600 cfm for a room the size of mine do you run your fan 24/7 or just when 1000 watt is on thanks for your help.also I live under the bridge in west Michigan


----------



## Dman1234 (Feb 16, 2015)

sopappy said:


> And I promised I wouldn't do that.... my apologies, Stickbait
> Good thing TheHempGoddess is keeping an eye on me, thanks THG.
> I remembered that wrong... evacuate *at least* every 5 - 8 minutes....
> I should be running my exhaust fan for at least 2 minutes every 10 minutes but I'm poor so I go 2 minutes every 15 and shot off my mouth before thinking...  sheesh, I'm part of the very problem I whine about.



You should be running your exhaust 24/7. Running on intervals is not what THG is reffering too, she is saying cubic feet of room compared to CFM rating of fan, with a speed controller if needed, anyone worried about odour will tell you shutting exhaust off only causes a big stink! as well as some other issues.


----------



## Dman1234 (Feb 16, 2015)

stickbait said:


> I was thinking around 600 cfm for a room the size of mine do you run your fan 24/7 or just when 1000 watt is on thanks for your help.also I live under the bridge in west Michigan



Run it 24/7 your flower room is 165 cubic feet, so a 600 cfm will do nicely. You want to run it 24/7 for odour and proper air exchange, it will prevent serious issues like powdery mildew.


----------



## The Hemp Goddess (Feb 16, 2015)

Dman1234 said:


> You should be running your exhaust 24/7. Running on intervals is not what THG is reffering too, she is saying cubic feet of room compared to CFM rating of fan, with a speed controller if needed, anyone worried about odour will tell you shutting exhaust off only causes a big stink! as well as some other issues.


 
Dman is correct.  You run your fan all the time.  Turning it on and off multiple times an hour is hard on the fan.  And the fan does not take enough power that turning it on and off like this is going to save you much.  So no real upside to this and a lot of potential downsides.  Exchanging your air x number of times a minute refers to what your fan does when running all the time at full capacity.  I have a space a bit under 150 cu ft.  I run a fan that is capable of 448 cfm per minute, so my room exchanges the air almost 3 times a minute.


----------



## stickbait (Feb 16, 2015)

Man this is what makes site so good I was planning on running fan only when lights are on can you suggest a good fan to use sounds like im going to need a good one. do you run a intake fan also or not and what do you all use for intake filter im building room as tight as I can don't want any bugs or light getting in thank everyone for your quick response iam enjoying building this cant weight to start growing


----------



## pcduck (Feb 16, 2015)

I recommend a Vortex fan.

Old screens work well


----------



## Dman1234 (Feb 16, 2015)

Yeah you cant go wrong with a vortex, extremely well made and 10 year garantee i believe, they are a bit pricey and there are other options, but for piece of mind this is the way to go, most find that intake fans arent needed, just passive intake.


----------



## The Hemp Goddess (Feb 16, 2015)

I was trying to figure out how old my Vortex was.  I think it has to be probably 8 years old and still running fine.  LOL--I have a spare fan that sat in storage so long, I loaned it to a friend starting a grow up so they didn't have to try and buy everything at once.

I have never found need for an intake fan.  I put screen over my intakes, like duck mentioned.  I pull cool air from my crawl space to cool my lights.


----------



## yooper420 (Feb 16, 2015)

stickbait said:


> forgot to tell you grow room is in 32x40 poll barn and I live in Michigan also have t5 8 bulb in veg with a barn this size can I exhaust in barn and draw fresh air also


 


stickbait said:


> I was thinking around 600 cfm for a room the size of mine do you run your fan 24/7 or just when 1000 watt is on thanks for your help.also I live under the bridge in west Michigan


 
Born, raised, worked for and retired from the once great city of Flint. Been living in the U.P. for 10 years. I draw fresh air in and exhaust the old air out inside my garage with no problems for 6 grows spanning 3 years.


----------



## stickbait (Feb 17, 2015)

Hey yopper do you grow in winter if so how do you work heat if I run fan 24/7 in the winter it will suck cold air in when lights are off in If run heater it will run all the time thanks for any help you can give me


----------



## yooper420 (Feb 17, 2015)

Yes I do grow in the winter. My garden room is insulated on all 6 sides, sets up off thr cement floor. Winter time, have to close one of the intakes and run the 2" exhaust 24/7. Have ceiling fan on 24/7 also. Running the small exhaust fan 24/7 works better then the 8" one cycling on and off.


----------



## stickbait (Feb 17, 2015)

sounds like we have about same set up insulated on six sides is your barn heated if not what do you use to keep it warm when light are off and fan running also what do you mean by cei.ling fan


----------



## yooper420 (Feb 17, 2015)

Garage is not heated, garden room has it`s own heater. Don`t get much heat from my LED`s. Regular ceiling fan, like you would hang in your house.


----------



## sopappy (Feb 18, 2015)

Dman1234 said:


> You should be running your exhaust 24/7. Running on intervals is not what THG is reffering too, she is saying cubic feet of room compared to CFM rating of fan, with a speed controller if needed, anyone worried about odour will tell you shutting exhaust off only causes a big stink! as well as some other issues.




So far I've been getting away with it and I was considering CO2 so I wanted to try it. I also like the idea of pulling everything out full bore instead of just a slow steady stream from intake to exhaust. I can't help but think it would just be a "narrow" stream of air from the intake hole to the exhaust hole all day with lots of stale pockets which of course, is nitpicking.

I am running it steady now but hate those noisy speed controllers, I use a HI MED LO on MED on a 400Cfm fan which I'm hoping is 200CFM
THG is also right on it likely being hard on the fan winding up like that 6 times an hour to say nothing of the hydro draw which convinced me to go back to steady half speed 24/7 instead... besides, me playing with CO2 would be downright scary.


----------



## gottaloveplasma (May 21, 2015)

How many air exchanges would be considered to much?


----------



## sopappy (May 21, 2015)

The Hemp Goddess said:


> I don't quite understand your question?
> 
> snipped...
> 
> In the winter when it is cold, I use the exhaust air from the vegging space to help heat the flowering space during lights out.  I have a larger bathroom type exhaust fan located in the veg space that blows into the flowering space.  This alleviates the need for an auxiliary heater in the flowering space if it gets too cool.



Do you also have another fresh air intake for the flower? 
I had intake in veg, fan to flower, and flower to can and out.
I was chastised  and had to add a separate fresh air for the flower and exhausted (the stale veg air) directly to the can.
I just take input from the house (instead of outside) in winter.


----------



## sopappy (May 21, 2015)

gottaloveplasma said:


> How many air exchanges would be considered to much?



I'd say no such thing myself, the more fresh air, the better


----------



## gottaloveplasma (May 22, 2015)

Can't you make your plants drink to much they will get wind burned and nutrient burned if you don't tone down feeding.


----------



## gottaloveplasma (Jun 14, 2015)

keep in mind that if you have 600 cfm fan you will loose about 20% to scrubber.  Also bends sags and length of ducting... I've heard 10ft is 10% loss, don't know how true it is.  So you are liable to get only 70% or less cfm movement.  I believe its always better to go bigger than what you think you will need with proper dial for fan.  It's my 2 cents.  I've got a problem in my tent.  I'm ducting from light about 3' from floor then out tent.  I'm thinking the 4 ft above light may be causing some problems and should be ducted as well.  I'm using 8" fan and 6" ducting  I need to fix that as well.  I am doing like you and using air to cool heat from lamp.  That requires much  more cfm then the plant needs.  I think it is better to get closed circuit for lights and vent room for fresh air seperatly.  I didn't think my light would make as much heat as it is although its only raising temps about 6-7 degrees at canopy where I want it.  I have been having a/c trouble to.  Nothings easy lol.


----------



## yooper420 (Jun 15, 2015)

stickbait,
Come visit "Curmudgeonland...Home of the Old Farts Club" in the Coffee Table section. Just a bunch of old farts, some retired, some not, who grow weed and talk about it with like minded peeps. Stop by, we have "wake and bake" sessions every morning and through out the day.


----------

