need help on design setup for venting

I have a room in my basement I'm goign to convert into my grow room.

I'm planing big time on my venting so I'm figuring that mess out.

My question is A, can you convert 4" dryer duct into 4" PVC Plumbing tubes? I'm thinking about jsut running a vent straight out of the roof parallel to my existing vent.

Better yet, I can tap into that 4" pipe also, but can you vent an exhaust into the vent line for home plumbing? Or will it push the waste the wrong way or what ever? I'm wondering if I put a "y" into the vent line and shoot the fan towards it, will it all go out of the house? Not sure if that makes sense or not.

My big concern is running ducts off the side of the house. I don't want any things poping out the side of the house as I think it may draw attention. More so, I think the smell will dissipate better if I vent it through the roof. How much fan power do you need to push out on long runs of 4" duct work if I can't tie into to existing vent, or new vent out the roof.

Thanks for any tips and suggestions on venting.

What I'm envisioning is 3 rooms. ! for the budding. 1 small area for clonging and seeds, and 1 area for the mothers to veg out in. So I will branch 3 ducts to vent out the odor from these areas. Also I want to branch in 3 fresh air lines to vent these areas too. So the main run will be about 20-30 feet in or out of the house. Maybe 40 tops if I have to go around some things, but I think I can get a close straight shot with maybe 3 or 4 turns tops. How much CFM you think I need to push out 3 areas 40 feet?

a few things. first, how big are your rooms going to be? secondly, how are they going to be arranged? could you provide us with a rough schematic as to what you have in mind?

that being said, you want to figure out the square footage of each room, and therefore the total square footage you are going to be dealing with. the general rule is that you want to be able to evacuate all the air in a space once every 5 minutes. for example, if you have a room which is 8x8x8, you have a room which has 512 sq feet. you would need at least 102 cfm to properly move that air.

when it comes to filtration and exhaust, more is better. you want to be able to create negative pressure inside your grow spaces. this has the effect of drawing air in through any cracks or crevices in your growing space, rather than allowing stinky air out.

you might find your job will be more difficult in efficiently moving air if you try using several different splitters. the more bends and conjunctions you have in your airflow, the more resistance there will be because of back-pressure. keep this in mind as you are designing your system.

as far as exhausting out of your sewer gas exhaust, it would depend on how much air you're trying to move. the sewer gas exhaust serves two purposes, it keeps dangerous sewer gases from seeping into your home through your pipes, and it also helps your drains flow properly by preventing a vacuum from forming in your drains. i'm not sure how effectively adding an exhaust vacuum to your drains would affect your plumbing, but you should consider the possibility. that, and it may be possible to hear the fans running through your pipes given the amount of air you will need to be moving.

it might be easier to run a line up a central wall to the attic, and exhaust in there directly. if you're using carbon filters, you can even tie it into your dryer vent exhaust, but if you live in a cold climate, somebody might notice that you're running the dryer all the time.

i know this was long winded, but hopefully it helps. get us a sketch of what you're planning, and it will be a lot easier to help you more.

no man that was perfect. I think what is going to happen is that I'm goign to vent up out the attic on it's own branch and then on out of the house. The only thing I wonder now, is converting from 4 inch flexi duct to pvp pipe. I'll run the pipe straight out instead of the flexi duct. I'm just wondering what adaptors if any I'll need to connect the two types. Not sure if I'll need a neoprene sleeve or what.

AS what was mentioned above i would have to say as long as you can vent into something htat is already putting out air.the dryer situation is a concern if it is winter. my main thing would be anything that is constantly venting out air from your house. i would jsut have all your rooms exhaust into one pipe and then connect to the main outlet that you want to use.
it is 100% possible to connect the 2. i think maybe if you can slip the duct in the pvc that would work awesome.but i mean if you have to slip it over the pvc that would work to. all you would prob need to do is duct tape it and im sure no air owuld escape specially if it was tiht and a bitch to get onto the pvc pipe to begin with.

ya totally. I haven't looked yet as there isn't a need for it yet until I start the work and purchasing for the project, but I'm sure some where they have special cuplings for connect those type of pipes/duct