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Attic grow ventilation (chimney)

Hi, just looking for some advice on ventilating my future grow room.  


Next to where the groom will be is the chimney stack.  I was thinking that this could be an option for extracting the warm air to.  The only thing is that there is a flue liner in there.  If I was to bore a hole through the stack would the air still escape?  Could I manipulate the flue liner once the hole is made?


The other option a soffit vent but I'm not sure if I will have the clearance for a 6 inch duct. And adding a vent could compromise my stealth. 


I notice that some folk here vent by the eaves/soffit vents but I'm worried that if I do this it could lead to condensation in the loft.


All help much appreciated.


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Google "150mm duct to flat adapter"


If you choose the soffits..


Not sure what to suggest on the chimney I've never dealt with a liner.. is it your property or rented?  If it were mine I'd probably have a crack at removing a brick and see what's what but don't go fucking around like that if you aren't competent or the owner.


Probably easier to use the soffits even if you need to use 2/3 outlets instead of one.



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I need to get in the loft and have a dig around by the eaves.  The person who had the house before us has had soffit vents fitted, but, I found out this evening that the soffits were originally asbestos.  I'm not sure if the asbestos has been capped.  I should imagine if vents have been put in then the asbestos soffit would have been removed.  Will have to tread carefully there.


It's my house.  I'm not a builder but can do the odd job or two but I am wary of removing messing with the stack.  If I knew there was no flue I'd just bore into it.  I could still bore a hole but what to do with the flue?  I assume it is tied in in some way or another to the chimney pot/cap.  Do I bore then slice the flue and try and pull it through the hole?  But then the flue below will fall and that is a pain in the bum.  Going on the roof and pulling the bugger out isn't and option at the moment.



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If it's an old house it may well be a double lined flu too.

ie ceramic liner with a metal flu inside. I've seen that done. But you would know because to fit the ceramic flu you have to hack into the brick flu every couple of feet to insert the ceramic liner and cement it in place. That's one hell of a job to do........


if it were me (my stealth might not be as yours is) I go the soffit adaptor route.

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Is the liner attached to a wood burner? Be careful removing bricks from a chimney stack. If it's an old house you could be making more trouble for yourself. 

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House was built in the 70's.


It was a back boiler flue.


I think I'll get a duct to flat attachment and dump it by the soffits. Cant access the soffit or facia from the attic to make vents but I think there is a bit of air movement there via the soffit vent.  Depends if the old asbestos soffits were removed.

If signs of condensation I could alway extract back to the room below.

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