Design in progress

[Greenthumber]

How's it going everyone? About to begin construction of 12x8 flower room along side a 5x6 veg room in a basement and looking for advice on passive ventilation compared to both rooms having separate exhausts I'm worried if I do passive ventilation that I'll dump positive pressure into one room From the other? Or make it harder to control temp wise from room to room? What do you recommend from your experience with either? Thanks in advance

 

[Greenthumber]

How's it going everyone? About to begin construction of 12x8 flower room along side a 5x6 veg room in a basement and looking for advice on passive ventilation compared to both rooms having separate exhausts I'm worried if I do passive ventilation that I'll dump positive pressure into one room From the other? Or make it harder to control temp wise from room to room? What do you recommend from your experience with either? Thanks in advance

Here is a rough draft

 

[LifeLess]

Good Luck. Hard to get help around here anymore. I'm also resetting up a room but couldn't get anyone to even say hi. Must be a trade secret.

 

[Greenthumber]

Good Luck. Hard to get help around here anymore. I'm also resetting up a room but couldn't get anyone to even say hi. Must be a trade secret.

For the most part I have it figured out just trying to get opinions from people that have experienced both, I can be patient lol I was referred to this site from a friend and from browsing and word of mouth a lot of the people in here can be quite helpful

 

[Mikell]

Passive intakes should be double the size of the active outtake.

Why run an AC? It will cycle constantly, running up the power bill for minimal result. If outdoor temperature is too high I would be looking at a closed room

It would be preferable to separate, in my opinion. If something fails the issue is isolated.

 

[Greenthumber]

Passive intakes should be double the size of the active outtake.

Why run an AC? It will cycle constantly, running up the power bill for minimal result. If outdoor temperature is too high I would be looking at a closed room

It would be preferable to separate, in my opinion. If something fails the issue is isolated.

That's part of why I was considering doing separate was the whole isolation issue,

As for the Ac I'm not totally positive I'll need it yet but have it in the plans incase I do. I plan on eventually getting to a closer room set up but it will be a little bit before I can get to that,, The basment i will be in stays about 67-72 degrees year round but I know once I get some lights going that will increase quite a bit

 

[Dislexus]

How's it going everyone? About to begin construction of 12x8 flower room along side a 5x6 veg room in a basement and looking for advice on passive ventilation compared to both rooms having separate exhausts I'm worried if I do passive ventilation that I'll dump positive pressure into one room From the other? Or make it harder to control temp wise from room to room? What do you recommend from your experience with either? Thanks in advance

You could just have your intake hole be in one room, an exchange hole between both rooms, and your scrubber and output in the other room. Air comes in one room, flows to the other, and is scrubbed out, all the same negative pressure if everything is balanced.

My main worry is your vented lights system sucking/pushing smelly air out, I've seen threads about it in the past. Plus all that cleaning of the glass and reflectors or you lose light efficiency.

 

[Dislexus]

Good Luck. Hard to get help around here anymore. I'm also resetting up a room but couldn't get anyone to even say hi. Must be a trade secret.

Fix your post Lifeless, all you posted was "I": https://www.icmag.com/ic/showthread.php?t=345038

 

[Greenthumber]

You could just have your intake hole be in one room, an exchange hole between both rooms, and your scrubber and output in the other room. Air comes in one room, flows to the other, and is scrubbed out, all the same negative pressure.

I actually just ventured into a friend of the family's grow room today he had a Similiar setup as to what you're describing with a passive intake between the two rooms only difference is he has a mini split head unit in each room with two passive intakes between both rooms one going from the veg to flower room and one from the flower to veg room for extra air circulation and also had a cf scrubber in each room but kind of through me for a loop when he had a stand alone Ac unit exhausting air throug a carbon box to outside the house.. doesn't a mini split cover for the need to exhaust outside?

My main worry is your vented lights system sucking/pushing smelly air out, I've seen threads about it in the past. Plus all that cleaning of the glass and reflectors or you lose light efficiency.

!

As for the vented light system I plan on running that on its own intake and exhaust to not have the extra heat in the room, will they still pull out the dank smell?

 

[Dislexus]

Usually reflectors aren't perfectly sealed so by your sketch above it would be sucking some smell out of the veg room. Then, as you are pulling from veg light and pushing to flower lights, any leakage from your higher CFM aircooled lights in your flower room could offset the negative pressure being created by your lower CFM scrubbed flower room exhaust.

I am biased on the subject but you're going to have AC you may not even need to aircool the lights, making your setup simpler and less work to maintain. Also with AC you have the option of CO2 later on and that doesn't usually work well with the aircooled lights. You could have your AC and CO2 in your flower room, scrubbing but not exhausting, or you could exhaust into the remaining basement space, which is then drawn in passively through your veg room back into your flower room to be scrubbed and recirculated.

OR to maximize your space available in your flower room use the rest of the basement outside the rooms as the "lung" by moving the AC, DH, and CO2 outside of your flower room, and drawing in passively to the flower room, through it to veg, and scrubbing out of the veg back into the lung, all without air-cooled lights.

Really its all about what you prefer and who knows it may change. It would suck to buy too much equipment and be stuck with it, better to start with the least equipment option then buy more if you need it. Maybe order the lights first and slap them up temporarily just to see how much they bump your temps up?

 

[Dislexus]

I actually just ventured into a friend of the family's grow room today he had a Similiar setup as to what you're describing with a passive intake between the two rooms only difference is he has a mini split head unit in each room with two passive intakes between both rooms one going from the veg to flower room and one from the flower to veg room for extra air circulation and also had a cf scrubber in each room but kind of through me for a loop when he had a stand alone Ac unit exhausting air throug a carbon box to outside the house.. doesn't a mini split cover for the need to exhaust outside?

Sorry I missed this as you put it in my quote. What was the stand alone AC unit? Part of the minisplit system or an additional AC system?

 

[Greenthumber]

Usually reflectors aren't perfectly sealed so by your sketch above it would be sucking some smell out of the veg room. Then, as you are pulling from veg light and pushing to flower lights, any leakage from your higher CFM aircooled lights in your flower room could offset the negative pressure being created by your lower CFM scrubbed flower room exhaust.

I am biased on the subject but you're going to have AC you may not even need to aircool the lights, making your setup simpler and less work to maintain. Also with AC you have the option of CO2 later on and that doesn't usually work well with the aircooled lights. You could have your AC and CO2 in your flower room, scrubbing but not exhausting, or you could exhaust into the remaining basement space, which is then drawn in passively through your veg room back into your flower room to be scrubbed and recirculated.

OR to maximize your space available in your flower room use the rest of the basement outside the rooms as the "lung" by moving the AC, DH, and CO2 outside of your flower room, and drawing in passively to the flower room, through it to veg, and scrubbing out of the veg back into the lung, all without air-cooled lights.

Really its all about what you prefer and who knows it may change. It would suck to buy too much equipment and be stuck with it, better to start with the least equipment option then buy more if you need it. Maybe order the lights first and slap them up temporarily just to see how much they bump your temps up?

The lung method has been something I've been pondering as well but all in all just geting ideas pros and cons on each method people have used, the real test will be when I get everything hung and do some test runs. Tomorrow I will be getting the lumber and get started on framing walls throughout the week, I'm eager but trying to do things as good as I can with what I can and with the availabile funds to do so with. Thanks for your input and expertise

 

[Greenthumber]

Sorry I missed this as you put it in my quote. What was the stand alone AC unit? Part of the minisplit system or an additional AC system?

No it was an additional mobile ac unit that he exhausted outside a basement window through a charcoal box

 

[Dislexus]

The lung method has been something I've been pondering as well but all in all just geting ideas pros and cons on each method people have used, the real test will be when I get everything hung and do some test runs. Tomorrow I will be getting the lumber and get started on framing walls throughout the week, I'm eager but trying to do things as good as I can with what I can and with the availabile funds to do so with. Thanks for your input and expertise

I wouldn't call it expertise! lol. I have something similar in a very large walk-in-and-around two-door closet, except for a wall to split the room between veg/work and flower I put up a single frame of 2x4s with that bubble-wrap-mylar rolled insulation attached as the barrier. And now I am kicking myself thinking maybe I should've just split the room equally into two flipflopped flower rooms and built a big veg/momma cabinet, but I've already built the shelves for vegging so I have workspace in there, ehhh. Though this way I can conceal the doors behind a big custom bookshelf and keep my secret hobby contained. So no expert here just lots of reading and trial and error and second-guessing and occasional fantasizing.

No it was an additional mobile ac unit that he exhausted outside a basement window through a charcoal box

I guess the mini-split system wasn't cooling enough so he added the other system later, or vice versa? Some guys report they go ahead and add a second backup AC system as a contingency, and their electrical bill turns out to be lower running both, so maybe that. Ask him/her? You getting any help from this family friend?

Keep us updated on your buildout, its how we all learn from eachother. BTW take pics we all love buildporn (something I should do myself but I'm so goddamn paranoid).

 

[Greenthumber]

I wouldn't call it expertise! lol. I have something similar in a very large walk-in-and-around two-door closet, except for a wall to split the room between veg/work and flower I put up a single frame of 2x4s with that bubble-wrap-mylar rolled insulation attached as the barrier. And now I am kicking myself thinking maybe I should've just split the room equally into two flipflopped flower rooms and built a big veg/momma cabinet, but I've already built the shelves for vegging so I have workspace in there, ehhh. Though this way I can conceal the doors behind a big custom bookshelf and keep my secret hobby contained. So no expert here just lots of reading and trial and error and second-guessing and occasional fantasizing.



I guess the mini-split system wasn't cooling enough so he added the other system later, or vice versa? Some guys report they go ahead and add a second backup AC system as a contingency, and their electrical bill turns out to be lower running both, so maybe that. Ask him/her? You getting any help from this family friend?

Keep us updated on your buildout, its how we all learn from eachother. BTW take pics we all love buildporn (something I should do myself but I'm so goddamn paranoid).

Hey whatever works for the situation you have ya know lol luckily this time I don't have to worry about the whole containing it from any specific people. Yeah the other grower mentioned is a member of the spouses family and offered help if needed with the build.

I will definitely be updating along the way I myself am a lover of the build/grow porn lol I'll be getting the lumber later today and hopefully getting at it tomorrow

 

[DocTim420]

Sometimes you receive "information" on this site, then other times you get "wisdom" (information plus experience).

Regarding air cooling your lights, here is what I did and was blessed with a 5-8 degree temperature drop in my grow room's ambient air.

1. Use outside air (vents along the eaves) as the source of your cooling air.
2. Filter the air (I made DIY filter boxes with 4'x8' rigid styrofoam insulation sheets 1 1/2" thick').
3. Instead of daisy chaining your light fixtures together (the exhaust of the 1st light becomes the intake of the 2nd light, exhaust of the 2nd becomes the intake of the 3rd...) design the ducting so each light's intake air is sourced directly from the cool outside air.
4. Adjust your photoperiod so lights are on during the cool of the night/early morning and off during the heat of the day.
5. Where possible use rigid ducting instead of the flexible stuff. Less air resistance in rigid ducting--which will save you CFM's.
6. All my rigid ducting trunk lines (intake and exhaust) are on top and outside my grow room' environment. Having the intake lines inside the warmer grow room will cause water to condensate along the "cool ducts" (dripping on your plants--hmm, increasing the potential for powdery mildew). Also, having the warmer exhaust lines inside the grow room will also "heat" the air up a bit too.
7. Flex ducting will eventually be needed, but limit it to straight vertical runs from the ceiling to each light and attach rigid elbows the 6" or 8" openings on each light. What makes flex ducting inefficient are the turns (as in 90 degree turns). Loss of CFM of 20% or more is not uncommon when comparing straight runs of rigid and flex ducting, even more when turns are compared (rigid elbow vs flex).
8. Over spec your exhaust fan. The CFMs I wanted in a particular fan was rather pricey for a 6" size, but real affordable in the 8" size. Just had to pickup a 8"->6" reducer. I did the same for my scrubber, I have the jumbo CAN150 suspended from the ceiling and instead of using the suggested 12" fan, I have the "over spec" 14" CAN fan.
9. If your light fixtures are a few years old you might be sucking out some of the CO2 supplemented air, especially from air leaks around the glass seal. Replacing the seal is easy but a little dirty...or if you're lazy, taping the gaps with aluminum tape also works.

So air cooling my light fixtures with each receiving fresh-outside air dropped temps by 5 degrees during the summer. I'll take it.

Now, during winter I get a double bonus. The room temps not only dropped over 8 degrees, but the lamp hoods became "cold to the touch" causing my AC to actually cycle off for total of 20-30 minutes each hour. It seldom cycles off when lights are on during the summer months. LOL, who would have thought of using lamp hoods (instead of the AC) to cool the room down when lights are on...lol.

Hope my experiences can help you...and I live about 6 miles from the beach in So Cali, a place not known for cold night temps.

 

[Dislexus]

Greenthumber I assumed you're not in a legal state, is that so? The critical factor of air-cooling with odor control is the reflector hood construction, many are not quite sealed in their design, research your purchase carefully if that's your plan.

Got an update of your vision sketch?

 

[Greenthumber]

Sometimes you receive "information" on this site, then other times you get "wisdom" (information plus experience).

Regarding air cooling your lights, here is what I did and was blessed with a 5-8 degree temperature drop in my grow room's ambient air.

1. Use outside air (vents along the eaves) as the source of your cooling air.
2. Filter the air (I made DIY filter boxes with 4'x8' rigid styrofoam insulation sheets 1 1/2" thick').
3. Instead of daisy chaining your light fixtures together (the exhaust of the 1st light becomes the intake of the 2nd light, exhaust of the 2nd becomes the intake of the 3rd...) design the ducting so each light's intake air is sourced directly from the cool outside air.
4. Adjust your photoperiod so lights are on during the cool of the night/early morning and off during the heat of the day.
5. Where possible use rigid ducting instead of the flexible stuff. Less air resistance in rigid ducting--which will save you CFM's.
6. All my rigid ducting trunk lines (intake and exhaust) are on top and outside my grow room' environment. Having the intake lines inside the warmer grow room will cause water to condensate along the "cool ducts" (dripping on your plants--hmm, increasing the potential for powdery mildew). Also, having the warmer exhaust lines inside the grow room will also "heat" the air up a bit too.
7. Flex ducting will eventually be needed, but limit it to straight vertical runs from the ceiling to each light and attach rigid elbows the 6" or 8" openings on each light. What makes flex ducting inefficient are the turns (as in 90 degree turns). Loss of CFM of 20% or more is not uncommon when comparing straight runs of rigid and flex ducting, even more when turns are compared (rigid elbow vs flex).
8. Over spec your exhaust fan. The CFMs I wanted in a particular fan was rather pricey for a 6" size, but real affordable in the 8" size. Just had to pickup a 8"->6" reducer. I did the same for my scrubber, I have the jumbo CAN150 suspended from the ceiling and instead of using the suggested 12" fan, I have the "over spec" 14" CAN fan.
9. If your light fixtures are a few years old you might be sucking out some of the CO2 supplemented air, especially from air leaks around the glass seal. Replacing the seal is easy but a little dirty...or if you're lazy, taping the gaps with aluminum tape also works.

So air cooling my light fixtures with each receiving fresh-outside air dropped temps by 5 degrees during the summer. I'll take it.

Now, during winter I get a double bonus. The room temps not only dropped over 8 degrees, but the lamp hoods became "cold to the touch" causing my AC to actually cycle off for total of 20-30 minutes each hour. It seldom cycles off when lights are on during the summer months. LOL, who would have thought of using lamp hoods (instead of the AC) to cool the room down when lights are on...lol.

Hope my experiences can help you...and I live about 6 miles from the beach in So Cali, a place not known for cold night temps.

Hey doc thanks for the detailed help I will definitely be putting your rigid ducting input to use and will be running as much of the ducting I can above the room in between the ceiling joists I really like the idea of using cooler air to each intake of the air cooled hoods and I actually thought about doing so already but being how far north I am and In a basement our winters get very cold and also I would be to worried having the water and condensation running in my ducting from the only basement window I have and cause some serious problems so not ideal in my climate area, but I wI'll be running separate intakes to each and exhausting elsewhere in the home as extremely low cost heating method for the winter months... as far as the co2 goes I won't have to worry about that as of yet because I'm not running any to start and probably won't untill i go completely sealed and have a mini split installed

 

[Greenthumber]

Greenthumber I assumed you're not in a legal state, is that so? The critical factor of air-cooling with odor control is the reflector hood construction, many are not quite sealed in their design, research your purchase carefully if that's your plan.

Got an update of your vision sketch?

I am in a legal state thankfully, I was informed of this by a good friend that if you pull the air through the hoods is where most of your odor leaking comes from rather than if you push your outside air through the air cooled ducting instead of pulling that you won't have as much of an odor issue which makes sense to me, but being said I have the tubular style lights with the reflector over the tube rather than the glass open hood so I'll be able to seal those better imo

 

[Greenthumber]

As far as an updated sketch I don't have one yet but I do have some progress on the build