Attic Grow...........Ventilation

attic grow sealed room inside outer attic.
i want to know if anyone knows the best way to do the ventilation.

i have 2 x 6" in line fans.

1. i was going to hook one fan up to my 4" (all there is) roof inlet for my sewer pipe coming directly from the roof and through my sealed lights and vent the air in to the rest of the house to warm it as it will only be fresh air. but i am worried about water getting sucked in from the rain and being blown over the lights.
i will fit a durgo valve on to the cut lower half of the sewer inlet pipe to let the sewer breathe and to stop in coming sewer gases.

2. i was going to use the second fan as a passive intake directly from the outer loft area which is outside my sealed room and blast the smelly air up the chimney, with carbon filter of course.

my question is this.

would i be better just sucking the air for the passive fan from the 4" roof sewer pipe, if a little rain water gets in to the grow room i can wear that.
and suck the air from the outer attic outside my sealed grow room for the lights and in to the rest of the house.

also will there be enough holes and crevices in my attic to suck the fresh air through for the fans or will my attic go in to negative pressure as well as my grow room going in to negative pressure with my passive fan.

i am fkn puzzled.

surely someone can either agree with me or steer me on the right path.

also will the 4" inlet sewer pipe be enough for the 6" fan as i am sure i will not need to put the fan on full power surely.

i dont know if i under stand would water be able to get to the fan? just make shure its pointing kind of up so that if water gets in it will fall right back out because of gravity and how were you going to get the 6 inch fan in a 4 inch hole just bend the duct to make it fit?

just a thought for you ,if your doing this illegaly.Growing in the attic is very easy to spot with the police choppers FLIR

stickyicky0420 said:

i dont know if i under stand would water be able to get to the fan? just make shure its pointing kind of up so that if water gets in it will fall right back out because of gravity and how were you going to get the 6 inch fan in a 4 inch hole just bend the duct to make it fit?

Click to expand...

the 4" sewer pipe comes in to my attic from over and above my head and with the sucking force of the fan might suck water in too on a rainy day.
and with the sucking power of the fan i doubt if a slight bend at the bottom will help.
i take it you do not know what a 150mm duct reducer is.

smokejoint said:

just a thought for you ,if your doing this illegaly.Growing in the attic is very easy to spot with the police choppers FLIR

Click to expand...

do you know what Kingspan or Jablite is?

i want someone to answer my question,
not answer my question with a question.
if you do not understand then stick to pc grows.

oh well your good then,just giving you a heads up incase you didnt know.As for your ventilation.I think you could solve the water issue with extra ducting ,or putting a bend in the ducting.Do you really wanna intake through a sewer pipe though ,i don't know but would it not stink your grow room up with the smell of shit?...I would intake through chimney and out through sewer..

What I did was have two 6" holes in the chimney brest one for my fan and filter and one for my cool tubes outlet the inlet for my tubes is from the 4" sewer pipe which I put a cap on it looks like a pointy hat that over hangs the pipe and stops the rain then ive got two in lets in my room suckin air from the attic (no fans on them the fan and filter are enuff). As for back pressure is your loft space sealed or just your grow room cuz if the lofts not seal you wont get back pressure? In stead of haveing two holes in the chimney have one for your filter an vent your lights to the house......

smokejoint said:

oh well your good then,just giving you a heads up incase you didnt know.As for your ventilation.I think you could solve the water issue with extra ducting ,or putting a bend in the ducting.Do you really wanna intake through a sewer pipe though ,i don't know but would it not stink your grow room up with the smell of shit?...I would intake through chimney and out through sewer..

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Durgo stops the sewer smell comein up to the inlet...

ah ,i see ,nice 1

WeeGogs said:

i want someone to answer my question,
not answer my question with a question.
if you do not understand then stick to pc grows.

Click to expand...

lol you should stick to pc grows if your stuck on ventlation on a actic grow lol.

RoYalQuEenChEeSe said:

What I did was have two 6" holes in the chimney brest one for my fan and filter and one for my cool tubes outlet the inlet for my tubes is from the 4" sewer pipe which I put a cap on it looks like a pointy hat that over hangs the pipe and stops the rain then ive got two in lets in my room suckin air from the attic (no fans on them the fan and filter are enuff). As for back pressure is your loft space sealed or just your grow room cuz if the lofts not seal you wont get back pressure? In stead of haveing two holes in the chimney have one for your filter an vent your lights to the house......

Click to expand...

i had the idea of putting a cover over my roof vent pipe too, to stop rainwater being sucked in by the pressure of the fan, but............ my roof is 50 feet up and i dont have access through an attic skylight or window.
it is a closed roof.

i am going to cut in to the pipe on monday and fit the durgo on the bottom half to seal the sewer from smells, and the air admittance valve (durgo) will stop anti syphon in the down pipe.

then i am going to use the top half to aid with fresh air inlet.

WeeGogs said:

2. i was going to use the second fan as a passive intake directly from the outer loft area which is outside my sealed room and blast the smelly air up the chimney, with carbon filter of course.

my question is this.

would i be better just sucking the air for the passive fan from the 4" roof, if a little rain water gets in to the grow room i can wear that.
and suck the air from the outer attic outside my sealed grow room for the lights and in to the rest of the house.

also will there be enough holes and crevices in my attic to suck the fresh air through for the fans or will my attic go in to negative pressure as well as my grow room going in to negative pressure with my passive fan.

i am fkn puzzled.

surely someone can either agree with me or steer me on the right path.

also will the 4" inlet sewer pipe be enough for the 6" fan as i am sure i will not need to put the fan on full power surely.

Click to expand...

Don't ask for help and then be an asshole to the people who answer.
If you have a fan on your intake, then it's not a passive intake. It's an active intake. A passive intake would be something like an open hole.

I definitely wouldn't install your ducting to that pipe coming up from your roof unless you go into the roof and get a waterproof fitting on top of it. That's just asking for trouble.
You could possibly use that as a passive intake for the attic (again, passive means no fan) and exhaust air down into your house.

Hopefully you either live in alaska or have an AC unit up there, because it's going to be hot 6 months out of 12

Clown Baby said:

Don't ask for help and then be an asshole to the people who answer.
If you have a fan on your intake, then it's not a passive intake. It's an active intake. A passive intake would be something like an open hole.

I definitely wouldn't install your ducting to that pipe coming up from your roof unless you go into the roof and get a waterproof fitting on top of it. That's just asking for trouble.
You could possibly use that as a passive intake for the attic (again, passive means no fan) and exhaust air down into your house.

Hopefully you either live in alaska or have an AC unit up there, because it's going to be hot 6 months out of 12

Click to expand...

first i dont like asking a question and being asked a question.
my original question was straight forward with anyone that has half a brain.
i know the answers myself i have built lots of solid grow rooms but a second opinion helps.
i can hardly ask my fucking next door neighbour now can i.
i will say it to you in plain english read my fucking lips.

i have 2 fans

i have one fan sucking through a pipe from my roof straight through my sealed lights and out in to my house .

i have a second fan that sucks air in to my room from the left over attic space through a PASSIVE hole and vents it straight up the chimney sucking through a carbon filter of course.

to have passive intakes you still need a fan, but not to your knowledge.

oh and by the way i live in the highlands of scotland and its freeziing all the year round.

thats why i go on holiday somewhere hot 3 times a year.

First post in years.

Read my fucking lips. Way to be a complete ass when asking for help.