trouthugger
Active member
I think I'm going to vent intake and exhaust through the doors. Would it be better to cut vents in standard doors or to buy louvre vented doors and just open the vents for intake and exhaust? Open to suggestions.
Help deciding exhaust route for my tent closet microgrow
- Thread starter trouthugger
- Start date
Ca++
Well-known member
As you have run this closet before, you have an idea of noise/smell/RH in the bedroom. Will doors really help hide the grow?
Though I have been back n forth with ideas here, trying to offer many solutions, I know I would put a centrifugal extractor in the loft. You wouldn't hear it up there, and it would have the power to pull air through that door gap.
Talk of slatted doors hints that light leaks from the tent are not a problem. So you could just leave one open a bit. The one nearest the bedroom door, so nobody can see in, or think of it as being closed.
Strictly answering the question, I would use solid doors. You can get the air shot out cleanly through a hole in a solid door. Having both in&out in the doors, will make the tent recirculate most of it's air. You would need to get it out into the bedroom, and then the bedroom has some air exchange. The measure of which, is your last grow
Though I have been back n forth with ideas here, trying to offer many solutions, I know I would put a centrifugal extractor in the loft. You wouldn't hear it up there, and it would have the power to pull air through that door gap.
Talk of slatted doors hints that light leaks from the tent are not a problem. So you could just leave one open a bit. The one nearest the bedroom door, so nobody can see in, or think of it as being closed.
Strictly answering the question, I would use solid doors. You can get the air shot out cleanly through a hole in a solid door. Having both in&out in the doors, will make the tent recirculate most of it's air. You would need to get it out into the bedroom, and then the bedroom has some air exchange. The measure of which, is your last grow
trouthugger
Active member
Last grow I left the closet doors open. Want to fix this issue so that I can shut the doors of the grow to improve stealth. (If I really have to stealth up and the landlord is coming or something I could put the original door back on).
I agree the loft is the best idea but if I do it I want to do it right and that's a good bit of work to do in a rented house. Would want to vent all the way outside in the attic. Don't want to risk mold.
Ca++
Well-known member
I see.
The problem with ducting through the attic space to find a way out, is condensation within the duct as it cools.
I drew a tube type dehumidifier before, for extreme cold. It's on a slope so the water runs back towards the warm end. For your circumstance, the slope could be the other way. So drips come out the end the air does. You could also forget all the insulation. You could just use a metal pipe. Foil ducting even, if you can set it straight. Then if the extract air cools enough to reach dew point, it's water dripping out the ducting, you can catch. It's very unlikely though. I wouldn't be giving this much thought to be honest. Without exceedingly difficult circumstances, it will be fine. It's also very easy compared to hanging doors and such. With a result that looks landlord proof, all the time.
Back to the doors..
Slats will probably lead to boarding or lots of gaffer tape. You see, a 152mm duct is a nice snug fit in a 140mm hole. Most people cut a 152mm hole than realise how sloppy it is. Leading to lots of tape, or perhaps a top hat spigot plate. Cut the hole a little to small, and the helical wire of the ducting will screw through the hole. Not that fitting it would mean revolving the duct or anything, it will still pull through. It's just the helix turning it's way through, ensures the duct wall is snug in your hole. Making the hose very easy to pop in and out of a hole in a board, yet still stay firm and sealed without any tape. This is why you would probably use a board, even with louvers.
Blowing out the louvers is a restriction. The fan is not immensely capable. You are asking it to do the carbon, which it will. Perhaps you want it to be the reason air enters the tent. It's now working hard. Then you want a few corners. It's getting out it's depth. The slats is a step too far for an axial fan. I think it's axial? you didn't give a model number.
It's going to work as it's 6" on ~240w. However it will be running loud.
I just went back to your photo. The tent roof does have a clear shot at the top of the right hard door. I think you could look at a hard pipe solution, not flex. A louvered door could close up to the hard pipe. You wouldn't duct the inlet air. I really don't like blowing through the louvers, but it is a clear shot. Any other route is convoluted. So while you could have a decent hole elsewhere using flex, the duct run might be as bad as a hard pipe to the louvers.
Edit: Louvers are terrible. It's like you are flat out down the straight in your F1 car, and suddenly chicane. All the cars behind you are slamming on. It's not good.
The problem with ducting through the attic space to find a way out, is condensation within the duct as it cools.
I drew a tube type dehumidifier before, for extreme cold. It's on a slope so the water runs back towards the warm end. For your circumstance, the slope could be the other way. So drips come out the end the air does. You could also forget all the insulation. You could just use a metal pipe. Foil ducting even, if you can set it straight. Then if the extract air cools enough to reach dew point, it's water dripping out the ducting, you can catch. It's very unlikely though. I wouldn't be giving this much thought to be honest. Without exceedingly difficult circumstances, it will be fine. It's also very easy compared to hanging doors and such. With a result that looks landlord proof, all the time.
Back to the doors..
Slats will probably lead to boarding or lots of gaffer tape. You see, a 152mm duct is a nice snug fit in a 140mm hole. Most people cut a 152mm hole than realise how sloppy it is. Leading to lots of tape, or perhaps a top hat spigot plate. Cut the hole a little to small, and the helical wire of the ducting will screw through the hole. Not that fitting it would mean revolving the duct or anything, it will still pull through. It's just the helix turning it's way through, ensures the duct wall is snug in your hole. Making the hose very easy to pop in and out of a hole in a board, yet still stay firm and sealed without any tape. This is why you would probably use a board, even with louvers.
Blowing out the louvers is a restriction. The fan is not immensely capable. You are asking it to do the carbon, which it will. Perhaps you want it to be the reason air enters the tent. It's now working hard. Then you want a few corners. It's getting out it's depth. The slats is a step too far for an axial fan. I think it's axial? you didn't give a model number.
It's going to work as it's 6" on ~240w. However it will be running loud.
I just went back to your photo. The tent roof does have a clear shot at the top of the right hard door. I think you could look at a hard pipe solution, not flex. A louvered door could close up to the hard pipe. You wouldn't duct the inlet air. I really don't like blowing through the louvers, but it is a clear shot. Any other route is convoluted. So while you could have a decent hole elsewhere using flex, the duct run might be as bad as a hard pipe to the louvers.
Edit: Louvers are terrible. It's like you are flat out down the straight in your F1 car, and suddenly chicane. All the cars behind you are slamming on. It's not good.
trouthugger
Active member
I am a little confused by some of this, but sounds like you're saying louvre doors are a no.
Mold is my big concern in the attic. Sounds like you don't think that's an issue. I wish I was that confident. It doesn't even get that cold near me, zone 7B.
You seem very knowledgable about this, I wish I understood as much as you then maybe I wouldn't be worrying about this so much.
Can't start growing again until I solve this issue...
Ca++
Well-known member
Zone 7B?
I have never heard anyone use such a term. Agricultural zones, as defined by the gov, suggesting what to grow there.
That is much more use than you giving your state away. We grow similar things, but you can extend to peaches and kiwi. Not oranges are pineapples though.
I can't imagine any need to start tackling RH problems. Nobody is finding you moldy loft pics, as it doesn't happen. Damp issues as bad as freezing at -30 for sure. Loft timbers are treated though. A wet loft dries. I see you may have a dehu in the corner. You could blow your extract onto that as a very quick fix. If you did get a real cold spell and snow capped. A hole is quick enough to make, and quick enough to fix, if it didn't work out. I'm just offering these band-aid solutions as backup plans though. You really shouldn't need to switch to cupboard door venting.
AG zones.. I need to drop something good for you in return.
Houses often sit around 600ppm co2. Up from the 415ppm outside. Plants are made with co2. In bulk weight terms, food is much lower down the list. It would be nice to be drawing this house air through the plants. If instead you do the doors thing, you may actually get below 415ppm. These sort of co2 numbers matter at the typical 700ppfd of light. These sort of numbers are why it's 700ppfd. The loft vent is real product weight. Your ability to light your crop with what you have, will be effected by your choice here.
I know of a meter tent in a bedroom with the door and window open. Over the hall, a bathroom with it's extractor on. I think while not a meter, you should be able to think about how this tent in a room looks beside yours.
When the grower is home, One guy, co2 in the groom sits around 500. He is not really in the ventilation path to help much with his breathing. However when he goes out, the groom drops below 380ppm, where his meter no longer reads. From this, you can see co2 increases at least 25% when he gets home. Which is probably worth another 150ppfd of light before negative returns. I would need to look at some utilisation charts, but it's somewhere there. A very noticeable gain. When he's in the groom, the 1000ppm alarm goes off. Making your air handling of high importance.
You can get cheapo co2 meters now from Ali. Sold as air quality monitors. It's why he has a 1000ppm alarm.
I have never heard anyone use such a term. Agricultural zones, as defined by the gov, suggesting what to grow there.
That is much more use than you giving your state away. We grow similar things, but you can extend to peaches and kiwi. Not oranges are pineapples though.
I can't imagine any need to start tackling RH problems. Nobody is finding you moldy loft pics, as it doesn't happen. Damp issues as bad as freezing at -30 for sure. Loft timbers are treated though. A wet loft dries. I see you may have a dehu in the corner. You could blow your extract onto that as a very quick fix. If you did get a real cold spell and snow capped. A hole is quick enough to make, and quick enough to fix, if it didn't work out. I'm just offering these band-aid solutions as backup plans though. You really shouldn't need to switch to cupboard door venting.
AG zones.. I need to drop something good for you in return.
Houses often sit around 600ppm co2. Up from the 415ppm outside. Plants are made with co2. In bulk weight terms, food is much lower down the list. It would be nice to be drawing this house air through the plants. If instead you do the doors thing, you may actually get below 415ppm. These sort of co2 numbers matter at the typical 700ppfd of light. These sort of numbers are why it's 700ppfd. The loft vent is real product weight. Your ability to light your crop with what you have, will be effected by your choice here.
I know of a meter tent in a bedroom with the door and window open. Over the hall, a bathroom with it's extractor on. I think while not a meter, you should be able to think about how this tent in a room looks beside yours.
When the grower is home, One guy, co2 in the groom sits around 500. He is not really in the ventilation path to help much with his breathing. However when he goes out, the groom drops below 380ppm, where his meter no longer reads. From this, you can see co2 increases at least 25% when he gets home. Which is probably worth another 150ppfd of light before negative returns. I would need to look at some utilisation charts, but it's somewhere there. A very noticeable gain. When he's in the groom, the 1000ppm alarm goes off. Making your air handling of high importance.
You can get cheapo co2 meters now from Ali. Sold as air quality monitors. It's why he has a 1000ppm alarm.
trouthugger
Active member
Correct, Agricultural Zones! I learned about them for outdoor gardening as I'm studying and trying to plan a native garden the past few years.
Fascinating stuff about the CO2. I really need to figure out what I'll do. The loft would be perfect and great stealth. It freezes here but might only snow once a year. My attic is already hot as hell but I'm trying to get a ladder and get up there and investigate the venting situation. It has a lot of cockroaches and bugs up there I think...
Ca++
Well-known member
I have know lofts hotter than grow spaces. In which cases the lofts got cooler.
One consideration from a thermal image point of view, is neighbouring homes. In the 'little boxes, made of ticky tacky' scenario, all lofts tend to match, as all homes are made and insulated the same. In mixed developments, nothing matches. In the little boxes differ though loft conversions, heating/aircon use and perhaps bathroom extractors going straight up. The only real concern was 6 spots on the tiles like the side of a dice, where 600s hung. Any other differences are merely circumstantial. Though worth thinking about. It's the crop thief walking the little boxes estate that's the problem these days. Kicking in doors, to find somebodies model railway. If snow comes, there is always the option of opening the cupboard for a week or two, and just blowing into the bedroom. If you were to choose the loft.
One consideration from a thermal image point of view, is neighbouring homes. In the 'little boxes, made of ticky tacky' scenario, all lofts tend to match, as all homes are made and insulated the same. In mixed developments, nothing matches. In the little boxes differ though loft conversions, heating/aircon use and perhaps bathroom extractors going straight up. The only real concern was 6 spots on the tiles like the side of a dice, where 600s hung. Any other differences are merely circumstantial. Though worth thinking about. It's the crop thief walking the little boxes estate that's the problem these days. Kicking in doors, to find somebodies model railway. If snow comes, there is always the option of opening the cupboard for a week or two, and just blowing into the bedroom. If you were to choose the loft.
trouthugger
Active member
Is exhaust from a 225W LED really going to melt snow off my roof?
Ca++
Well-known member
It's not really the 225w of concern. It might lift the intake temp 4 or 5c, but that inlet air was lifted from near zero to maybe 24c by the house heating. So the 28c air entering the loft, is mostly heated by the house.
I have stuck a fan heater in a loft before, looking for real numbers. A lot depends on how well it's sealed. A snow cap is quite a good seal.
There are such a multitude of variables, including the weather. I'm sure it will work, but having other plans in place now, is never a bad thing. Then if you do end up with problems, you know a few fixes without loosing time asking later. I can't promise anything without seeing your exact circumstances, but as a rule of thumb it seems fine.
I would have the fan up there, so if I did need to change things, then blowing back through the loft hatch would be high on my list.
If the fans in the tent, you blow out the cupboard door till any situation passes. Which might be simply paranoia of coming snow or a real cold snap. Remember, when it's bloody cold outside, you might want to keep that extract and dehumidify it. As pulling fresh air into the house to feed the tent, is a cold draft.
Keeping things flexible and in a state of readiness, is just good practice.
Three Berries
Active member
Do not exhaust to the attic if the temp gets below 40F. Been there done that.
Ca++
Well-known member
That is a very sweeping statement. There are many variables. Too many to apply numbers. We need a lot of surrounding data to make that 40f claim touch any bases.
Three Berries
Active member
All you need to do is see what the RH and temp is going out and drop the temp to less than 40F. I guarantee you will be getting condensation. My exhaust is usually 83F and 72% leaving the tent. You should see that at 0F.
Never had an issue of condensate coming down the steel pipe though as there was always flow out keeping the pipe at near the same temp. Only a short piece was actually exposed in the attic.
trouthugger
Active member
@Ca++ @Three Berries this is the kind of conversation I was hoping for. Thanks guys...
Three Berries
Active member
I vented out the attic for about 6 years with just an 150 cfm bath exhaust fan. Not much of a noticeable problem. But I was not adding any humidity like I do now. I might go though over 1 gallon a day for the flower tent when it's really dry air in the winter.
trouthugger
Active member
I'm just worried about damaging the rental. I really don't know enough to properly vent into the attic and exhaust it out of the attic.
I'm thinking of just making a vent in the closet doors.
trouthugger
Active member
Think I have decided I must exhaust through the door. I will be cutting a large intake vent on the left side door for my passive intake. On the right side I plant to cut a circular hole for my 6" exhaust.
I need to figure out a way to fasten the duct flush to doorframe flush to the exhaust hole. This is so I can still open both doors without disturbing the exhaust ducting. Does anyone have any idea what hardware I should be looking for to mount a 6" duct to the doorframe some how?
Here's an arial view of the tent and closet to illustrate:
I need to figure out a way to fasten the duct flush to doorframe flush to the exhaust hole. This is so I can still open both doors without disturbing the exhaust ducting. Does anyone have any idea what hardware I should be looking for to mount a 6" duct to the doorframe some how?
Here's an arial view of the tent and closet to illustrate:
trouthugger
Active member
Duct Wall Strap would something like this work to mount the duct to the door frame so I can still open and close the door?
moose eater
Well-known member
Does your landlord/home owner mind if cut holes in their closet or walls?
If the answer is yes, then maybe creeper's recommendation to hang a curtain, and outside of that room, run an air cleaner/deodorizor in an internal loop in the area adjacent to the closet?
Many times growers have made a poor statement for the movement/iother growers by doing things to a homeowner's place that weren't cleared or even announced. Some cases way worse than others, of course.
If the answer is yes, then maybe creeper's recommendation to hang a curtain, and outside of that room, run an air cleaner/deodorizor in an internal loop in the area adjacent to the closet?
Many times growers have made a poor statement for the movement/iother growers by doing things to a homeowner's place that weren't cleared or even announced. Some cases way worse than others, of course.
trouthugger
Active member
I am not supposed to cut big holes in the wall but can patch them easy enough. My current solution I'm leaning towards is buying a new set of doors to modify with vents and then keep the landlords doors untouched to replace when I move out or when he visits.
