Installing bathroom vent fan in condo with common vent (pics)

Mikepier

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Apr 6, 2011, 6:45:42 AM4/6/11

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Doing a reno job in a condo, we gutted the bathroom that had a common
duct riser for the condos above. I don't know if there is a fan on the
roof or not. But Is there any reason I can't put in a vent fan of my
own to force the air up this duct? I believe the duct is made of some
kind of concrete, or possibly asbestos? How is this usually dealt
with?
It was originally a wall vent, so I would have to get a wall mount
fan.

https://picasaweb.google.com/mikerock92/CondoVentFan02?feat=directlink

RBM

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Apr 6, 2011, 7:04:35 AM4/6/11

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"Mikepier" <mike...@optonline.net> wrote in message
news:ba0f2452-1839-461a...@e21g2000yqe.googlegroups.com...

** If the duct is common to several units, and was made for bathroom
ventilation, I would expect there is a roof mounted blower. If you connect
your own fan to the duct, and there is nothing pulling the air up, and there
are no backflow preventers, your air is going to go into other units

jamesgangnc

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Apr 6, 2011, 8:06:42 AM4/6/11

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On Apr 6, 7:04 am, "RBM" <r...@live.com> wrote:
> "Mikepier" <mikep...@optonline.net> wrote in message

I concur. If it's a shared duct then you have to use a blower at the
top to "suck".

John Grabowski

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Apr 6, 2011, 7:59:53 AM4/6/11

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>> Doing a reno job in a condo, we gutted the bathroom that had a common
>> duct riser for the condos above. I don't know if there is a fan on the
>> roof or not. But Is there any reason I can't put in a vent fan of my
>> own to force the air up this duct? I believe the duct is made of some
>> kind of concrete, or possibly asbestos? How is this usually dealt
>> with?
>> It was originally a wall vent, so I would have to get a wall mount
>> fan.
>>
>> https://picasaweb.google.com/mikerock92/CondoVentFan02?feat=directlink
>
> ** If the duct is common to several units, and was made for bathroom
> ventilation, I would expect there is a roof mounted blower. If you connect
> your own fan to the duct, and there is nothing pulling the air up, and
> there are no backflow preventers, your air is going to go into other units

*If there is a roof mounted fan, there is no guarantee that it is actually
in working order. Some roof mounted items don't always get proper
maintenance. Find out from condo management if there is a fan and if it is
working.

Evan

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Apr 6, 2011, 4:05:30 PM4/6/11

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Ummm... Dude... The picture of the hole is really useless...

What did you remove when you gutted ? Was it just an air grille
or was there a powered fan in place in your bathroom to feed
the air into the common duct ?

The issue brought up by RBM is a valid one:

** If the duct is common to several units, and was made for bathroom
ventilation, I would expect there is a roof mounted blower. If you
connect
your own fan to the duct, and there is nothing pulling the air up, and
there
are no backflow preventers, your air is going to go into other units

**

So it is more important what you removed in the demo process
which will help you identify what was in place on that duct so you
have some clue as to how the other units might be equipped...

John Grabowski also offered some wise advice:

*If there is a roof mounted fan, there is no guarantee that it is
actually
in working order. Some roof mounted items don't always get proper

maintenance. Find out from condo management if there is a fan and if
it is
working.*

You need to ask permission to connect to common elements which
are provided for the use of multiple units in a condo development...
This will often be done at a meeting where you present your approved
plans for the remodel from the AHJ and ask to reconnect to the vent
duct which you have disconnected yourself from...

You would then be informed of how that connection is to be made,
what sort of devices are currently required and possibly the
specifically
approved contractor the condo association/board has approved for
that purpose because it is a common element you wish to connect
to, not something which belongs to your specific unit...

Good luck with this... Word of caution, condo associations generally
don't let persons without the proper licensing modify or touch common
elements -- you will also be asked to provide a certificate of
insurance
before you are allowed to modify any of the association controlled
common elements...

~~ Evan

Mikepier

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Apr 6, 2011, 8:05:54 PM4/6/11

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>
> Ummm... Dude... The picture of the hole is really useless...
>
> What did you remove when you gutted ? Was it just an air grille
> or was there a powered fan in place in your bathroom to feed
> the air into the common duct ?

Just a simple wall grill.

hr(bob) hofmann@att.net

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Apr 7, 2011, 11:20:25 AM4/7/11

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WHy do you need a fan? .Have you tried a smoke test to se if there is
a drawing in of air at the hole in the wall?? Do you get noise from
adjacent units, that might tell you if it is a shared vent or not??
Too much unknown to make a rational response.