Very Big Room - Do I Have to Vent Outside?

[shamrockceo]

Hey Everyone,

This is my first post here, but I've been a lurker for a while before this. Lots of good info here, I'm loving it!

Now, I'm trying to wrap my head around everything involved with growing, so I can plan my first grow. But I'm taking my time because I want to do it right the first time. Something I'm stuck on currently is ventilation. Up front, I REALLY don't want to vent outside my house at all, period.

I'm planning to use a Blackdog 750 XL Platinum LED light for flowering, and possibly more LED lights for clones, mothers and vegging. I haven't fleshed the light situation out fully just yet, but I imagine I'll be using the equivalent of 2,000 watts of LED lighting for my whole setup, or so.

With that said, I'm going to be using Gorilla Grow Tents in a very large room in my basement. The room will have nothing at all in it except for my grow. The room is 26 feet x 18 feet and 8.5 feet tall. There's some dips in the ceiling in some places for ductwork and mechanicals of the house, etc. So I'm going to say the room is roughly 3,700 cubic feet of space. The room is finished and will be air conditioned to 69 degrees.

So my question is, can I vent my tents into this same room and be safe as far as heat and smell goes? I'm planning to use good, large, carbon filters and possibly an ozone generator (still researching ozone, since apparently it's bad for us), if I can do that safely indoors with that large room.

 

[JohnDee]

Hi,
Your AC should provide enough fresh air in. I wouldn't bother with outside ventilation in that space. There's always the odor risk even with carbon scrubbers...so another reason for no outside outlet. I grew for two years in a mobile home and had no outside vents and no plant problems.
Good luck,
JD

 

[shamrockceo]

Awesome, thanks JD, that's reassuring! Anyone else have any thoughts? Should I be alright in terms of humidity, mold, and any other things I may not be thinking of? All thoughts welcome, I want to hear as many different viewpoints and opinions as possible.

 

[shamrockceo]

Hi,
Your AC should provide enough fresh air in. I wouldn't bother with outside ventilation in that space. There's always the odor risk even with carbon scrubbers...so another reason for no outside outlet. I grew for two years in a mobile home and had no outside vents and no plant problems.
Good luck,
JD

Also JD, what type of light(s) and fan(s) were you using? Did you use ozone?

 

[shamrockceo]

bump, anyone?

 

[Green Thumb MN]

Give it a try. Worst case you go to plan B.

 

[ratsofftoya]

I'm not very experienced so don't take this as definite, but I don't see any problem with that whatsoever.

 

[JohnDee]

Shamrock,
Hi...in my MH, I had the largest bedroom dedicated to growing. I had around 1500 watts in flower room and another 800watts in veg and clone area. I vented the flower room from the veg room using only about 300cfm fan (if memory serves). I had two medium sized scrubbers and you could not smell grow room from rest of trailer. No outside venting.

In your basement op, you may have humidity issues and for that, you may have to get dehumidifier. Depends on how damp your basement is. Some are nice and dry. Good luck,
JD

 

[AimAim]

My grow room is 5X5' in an unfinished partial basement about the size of your room. I draw air from, and vent air back into this basement. It's naturally cool, and does have some air exchange with upstairs. The ductwork is there if I need to use heat or AC, but the normal temp of the basement runs mid 60s which makes climate control easy.

 

[Ammastor]

Hi,
Your AC should provide enough fresh air in. I wouldn't bother with outside ventilation in that space. There's always the odor risk even with carbon scrubbers...so another reason for no outside outlet. I grew for two years in a mobile home and had no outside vents and no plant problems.
Good luck,
JD

This will depend on your A/C. Most A/C unites circulate the air in the room and do not pull from outside. Most window A/Cs are only in windows because they need a place to release condensation and to cool the coils. The A/C coils the air in the room passes over again and again to cool the air. The reason why they are called an air conditioner. Just saying most do not pull air from outside. But just circulate the air inside.

 

[JohnDee]

Greetings,
I stand corrected...thanks Ammaster. Certain ACs do have a mode whereby a certain amount (around 10%) is exchanged...so be sure to get one with that feature. Fedders ACs call this aptly: the "air exchanger" and is switch controlled.
JD

 

[BustinScales510]

One of the main reasons for venting is to exchange the air. The plants use the c02 thats in the air and breathe out oxygen. The thinking is that if it is a closed environment with a lot of plants they might use up all the c02 in the air and be left without enough to grow well. People that dont vent usually supplement c02 with a tank or a gas burner. There are meters that will show the c02 level in the air, normal is about 300 I think. You can see how well the plants do and if there are growth issues you could look into that.

 

[JohnDee]

Bustin,
Shamrock doesn't want to vent outside but is having his grow space inside a large room...I'm of the opinion that it's ok to do so.

But let me add some details to my previous post describing my MH grow room. The basic room was spit in two...far end being bloom room. I had passive "darkroom vents" for air into bloom room and a 256cfm fan through carbon scrubber to exhaust bloom room into veg room..

The veg room also had a 256cfm fan through scrubber exhausting to the living quarters and also had passive vents for intake air.

The whole shabang also relied on the fact that I opened the doors several times a day and the living area also get fresh air from door opening and such.

I am assuming your grow space won't occupy the whole room but will be built inside of that large room...correctomundo?

I never had any problems with plants in two years of use.
JD

 

[skunkd0c]

The main factor will be co2/fresh air as other folk have already said
i guess it could be all worked out if you get all the variables
and know how much co2 a certain amount of plants will use roughly
compared to the amount of cubic air space you have
if you only grew 1 plant with 1 light in a very large closed space of course it would be fine, but as you build up the numbers it will reach a point where
they will suffocate

peace

 

[Ammastor]

Greetings,
I stand corrected...thanks Ammaster. Certain ACs do have a mode whereby a certain amount (around 10%) is exchanged...so be sure to get one with that feature. Fedders ACs call this aptly: the "air exchanger" and is switch controlled.
JD

No problem. Just wanted to point that out. So he knows what to look for if he purchases one. Either way though if he is venting out of the room might not need a unit that exchanges.

One of the main reasons for venting is to exchange the air. The plants use the c02 thats in the air and breathe out oxygen. The thinking is that if it is a closed environment with a lot of plants they might use up all the c02 in the air and be left without enough to grow well. People that dont vent usually supplement c02 with a tank or a gas burner. There are meters that will show the c02 level in the air, normal is about 300 I think. You can see how well the plants do and if there are growth issues you could look into that.

Gas burners work really well. As long as you have total control over your environment.

 

[dodadamthang]

Something I'm stuck on currently is ventilation. Up front, I REALLY don't want to vent outside my house at all, period.

I imagine I'll be using the equivalent of 2,000 watts of LED lighting for my whole setup, or so.

With that said, I'm going to be using Gorilla Grow Tents in a very large room in my basement. The room will have nothing at all in it except for my grow. The room is 26 feet x 18 feet and 8.5 feet tall. There's some dips in the ceiling in some places for ductwork and mechanicals of the house, etc. So I'm going to say the room is roughly 3,700 cubic feet of space. The room is finished and will be air conditioned to 69 degrees.

So my question is, can I vent my tents into this same room and be safe as far as heat and smell goes? I'm planning to use good, large, carbon filters and possibly an ozone generator (still researching ozone, since apparently it's bad for us), if I can do that safely indoors with that large room.

Hey Shamrock i have to chime in here... I respect all the other opinions here highly but I strongly suggest you reconsider your setup. I like it all except for the no venting outside part. lol. I am just concerned that you will have issues down the road with exactly those things... smell, humidity, temps, etc.

In the basement too right? Have you ever heard of the stack effect? its the way a lot of homes breath (especially in the Northeast). No time for a lecture here but you could change the way the house breaths.

I dont think you will get the control you want doing it like this but if you add a lung room (breather room?) then you will be much better protected. I would do it with the lung room but otherwise you will just be exchanging the air in the tents so much that the room environment will not be much different than the tent environment(humidity, temp, smell, etc.)The air in the basement generally ends up traveling through the entire house(stack effect). Take care friend. Dont rely on carbon filters too much! You may be disappointed.

 

[JohnDee]

Shamrock,
Question...your reason for not wanting an outside vent, Stealth? Neighbors nearby?

I don't know what Dodad is talking about, but his advice is internally inconsistent. He wants you to vent outside but also to not trust carbon filters? Seems that puts you in a bit of a bind! lol
JD

 

[shamrockceo]

Lots of good replies and info, thanks everyone! The entire basement is about 2,000 sqft, with the grow room being about 450 sqft. I can leave the door to the grow room open about 95% of the time, which I'm hoping will take care of any humidity issues, with the AC being pumped into the room with central air, and the passive air leaking out of the open door. The only time I would have to keep the door to the grow room closed is when I have family visiting, which is only maybe 2 weeks a year, or so - I could possibly even just work around these visits to not be growing at these times, but I wanted to do a sea of green type setup, so we'll see.

This will depend on your A/C. Most A/C unites circulate the air in the room and do not pull from outside.

I have central AC throughout the entire house, there's no window AC unit. Does this make a difference? I assume a central AC system pulls fresh air from outside to have fresh air inside the house at all times, but this isn't my field of expertise, haha.

One of the main reasons for venting is to exchange the air. The plants use the c02 thats in the air and breathe out oxygen. The thinking is that if it is a closed environment with a lot of plants they might use up all the c02 in the air and be left without enough to grow well. People that dont vent usually supplement c02 with a tank or a gas burner.

While I was hoping to not have to vent to another room or outside directly, the room is not a closed environment, except for the tents. AC will be pumped in and air will leak out of the room via the open door. How does this effect co2 in this situation, should it be fine? I'm planning on having 20 plants in flower at one time (5 plants in each of the 4 stages of the sea of green setup I'm planning on adopting), in addition to a few mothers and a bunch of clones. Compared to some of the setups I've seen on this forum in even MUCH smaller spaces makes me think my setup will be very small in comparison. With that amount of plants, should I be good on co2?

Bustin,
But let me add some details to my previous post describing my MH grow room. The basic room was spit in two...far end being bloom room. I had passive "darkroom vents" for air into bloom room and a 256cfm fan through carbon scrubber to exhaust bloom room into veg room..

The veg room also had a 256cfm fan through scrubber exhausting to the living quarters and also had passive vents for intake air.

The whole shabang also relied on the fact that I opened the doors several times a day and the living area also get fresh air from door opening and such.

I am assuming your grow space won't occupy the whole room but will be built inside of that large room...correctomundo?
JD

What are "darkroom vents", can you explain more on that? The door to the large room where my tents will be will be open 95% of the time, so similar to yours. The rest of the house will get fresh air from door openings (although not very frequent, maybe 1-4 times a day), as well as from the central AC pulling in fresh air, if I'm correct in thinking that it does that.

And that's correct, I'm thinking of using a gorilla grow tent, about 5' x 5' for the 4 flowering phases of a sea of green setup (20 plants total). Then I'll have a smaller tent to house the mothers and clones. So my actual growing area will be drastically smaller than the room that has the tents in it.

The main factor will be co2/fresh air as other folk have already said
i guess it could be all worked out if you get all the variables
and know how much co2 a certain amount of plants will use roughly
compared to the amount of cubic air space you have
if you only grew 1 plant with 1 light in a very large closed space of course it would be fine, but as you build up the numbers it will reach a point where
they will suffocate

peace

I'm planning on having 20 plants in flower, 2-3 mothers, and then a bunch of clones. Should that be fine with the given space, for co2 and fresh air?

Hey Shamrock i have to chime in here... I respect all the other opinions here highly but I strongly suggest you reconsider your setup. I like it all except for the no venting outside part. lol. I am just concerned that you will have issues down the road with exactly those things... smell, humidity, temps, etc.

In the basement too right? Have you ever heard of the stack effect? its the way a lot of homes breath (especially in the Northeast). No time for a lecture here but you could change the way the house breaths.

I dont think you will get the control you want doing it like this but if you add a lung room (breather room?) then you will be much better protected. I would do it with the lung room but otherwise you will just be exchanging the air in the tents so much that the room environment will not be much different than the tent environment(humidity, temp, smell, etc.)The air in the basement generally ends up traveling through the entire house(stack effect). Take care friend. Dont rely on carbon filters too much! You may be disappointed.

Hmm, I will have to look more into this, didn't even think about anything like this at all. But as far as carbon filters, I don't know of another way to control smell - maybe ozone or ona gel? I'm not really familiar with either of those, but maybe I should look into them? Does everyone else agree that I shouldn't rely on carbon filters too much for smell? I was planning to rely SOLELY on them, by just buying larger ones than I needed, sort of an overkill effect.

Shamrock,
Question...your reason for not wanting an outside vent, Stealth? Neighbors nearby?

I don't know what Dodad is talking about, but his advice is internally inconsistent. He wants you to vent outside but also to not trust carbon filters? Seems that puts you in a bit of a bind! lol
JD

Both reasons are valid for me. For some reason, I just feel safer having the entire grow confined to the interior of my house. Venting outside would make me very paranoid. In addition to that, it's a brand new home being built, and I don't want to cut holes in it right off the bat - not to mention I'm not handy with things like that and I can't exactly hire someone to do it, lol. So it's just all around easier to not have to vent anywhere, if it's not necessary.

 

[skunkd0c]

i think you will get away with it, if they are 20 medium sized plants few oz each and there is plently
of room space left without plants in it

since you say air is going to leak out of doors n such, you should just vent it

when you do not control the air it will just sit there and become humid/stale
air does not move unless you direct it and cause a flow due to presure change
air just leaking out of doors will cause wafts of smell to escape, its much better to control airflow in 1 direction

if you are worried about sound and smell leaking out and avoiding extracting because of this
you could overcome these issues with the right equipment

although i think you will get away with your idea, it would be so much easier if you could overcome
whatever issue that is stopping you vent directly out, you can vent to another part of the house through the ceiling/floor/walls etc
it does not have to be directly outside the property, you are creating yourself much more work and cost and possibly even problems by avoiding
proper air control , if your dead set on it, maybe look into co2 enrichment and humidity control, also maybe even ozone
you might have to deal with other issues like mold PM, as you are using a basement damp could be an issue

peace

 

[JohnDee]

Shamrock,
With a new house, your basement should seal good and hopefully not too humid. It's old basements with cracks and such that tend to leak in high water season.

Darkroom vents are made for old school photographers who develop and print pictures on film and paper. Soon to be a thing of the past I suspect. They are lightproof vents...perhaps 15" square with louvers designed to block light yet allow ventilation. Just passive...no fan. I don't think you'll need any, but Adorama, a NYC mail order place, might still sell them. Cheers,
JD

PS: Dodad, didn't mean to besmirch you...just have no knowledge of those issues.