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Discussion Starter · #1 · (Edited)
What are you folks typically using for your 5'x8' bathroom remodels? 80 cfm fans or 110 cfm? How about 5' x 11' rooms? Just curious. For the Panasonic folks, which series of their fans?
 

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Talking Head
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Whenever possible, I use a remote mount fan from my electrical supplier. It's a little over 150 cfm so i can run two grills off it. One over the shower and one over the toilet. It's pretty quiet to begin with and moving it a few feet away makes it VERY quiet. I've realized that if a fan gets too quiet you need to have it switch on a light circuit or people will forget to turn it off.

I'll have to check an invoice for the brand.
 

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Discussion Starter · #4 ·
Whenever possible, I use a remote mount fan from my electrical supplier. It's a little over 150 cfm so i can run two grills off it. One over the shower and one over the toilet. It's pretty quiet to begin with and moving it a few feet away makes it VERY quiet. I've realized that if a fan gets too quiet you need to have it switch on a light circuit or people will forget to turn it off.

I'll have to check an invoice for the brand.
I've never done a remote fan, but this job might be ideal for it. Two adjacent bathrooms and I can partially get to them from above (access behind kneewall.) They will be vented out the gable.
 

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I ve used most of them and Panasonic is the better end. With remote units I have used FanTech.

I recently ran into a problem with these. Its wasnt my install I was looking at windows for a client when it mentioned his fan not working or making noise. I looked in the attic and there was excessive slack in the duct whcih sagged between ceiling joist. Because these units dont have sloping ducts there was moisture building in the sags of the line to the point where we were draining water & blocks of ice out of it into a bucket from the diffuser. Good thing is it didnt burn out the motor and worked like a champ afterwards.

So no slope, excessive sag and no insulation is bad news.
 

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I've never done a remote fan, but this job might be ideal for it. Two adjacent bathrooms and I can partially get to them from above (access behind kneewall.) They will be vented out the gable.

They need to be corded and plugged so that means they must remain accessible.
 

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They need to be corded and plugged so that means they must remain accessible.
Definitely.

I'm currently installing one for a basement remodel and will have to get creative with condensate drainage as the fan had to mount to the bottom of the joists in an adjacent storage room so it's at the low point of the run.
 

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Definitely.

I'm currently installing one for a basement remodel and will have to get creative with condensate drainage as the fan had to mount to the bottom of the joists in an adjacent storage room so it's at the low point of the run.

I believe the coil of the flex is designed to help the exhaust vortex. Its a hassle for installing. I dont know why its not allowed to use light guage PVC, I used to use that and slide a 6" insulated duct sleeve over it. It was nice. Covered a few bases.
 

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I believe the coil of the flex is designed to help the exhaust vortex. Its a hassle for installing. I dont know why its not allowed to use light guage PVC, I used to use that and slide a 6" insulated duct sleeve over it. It was nice. Covered a few bases.
I didn't know you couldn't use pvc drain pipe. Some manufacturers even suggest it.

Is that a local thing?



Delta
 

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Always Learning
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Sdr 35 piping works nice for bath fans. You will get closer to the advertised cfm rating with smooth pipe over flex. The flex actually creates turbulence which reduces cfm. In HVAC runs, guys will use 7" flex to get the same cfm as a 6" metal gets.
 

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I didn't know you couldn't use pvc drain pipe. Some manufacturers even suggest it.

Is that a local thing?



Delta
My plumber told me your no longer allowed. IDK seems old to me but he has 5 licenses and part time inspects. Should have broke his balls and made hime produce a citation.
 

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I always use this little link after measuring the bathroom, and then round up.

http://www.ventingdirect.com/bath-exhaust-fan-calculator/c16459

Panasonic is king, but the installation of the bar hangers can get a bit time consuming. They have certain screws that lock in certain things depending on the joist spacing. But the quality cannot be beat.

In second place, the Air King line is a little less expensive but the quality is almost as good in my experiences.
 

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RS could you verify the code question?

Speaking of Overanalyze... I think if the coil of flex goes against the rotation of the fan you get better velocity from smooth pipe because of static pressure. So your right unless the fan was perpendicular to the flex & going in the proper direction there would be no benefit.
 

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RS could you verify the code question?

Speaking of Overanalyze... I think if the coil of flex goes against the rotation of the fan you get better velocity from smooth pipe because of static pressure. So your right unless the fan was perpendicular to the flex & going in the proper direction there would be no benefit.
That could be. I was speaking more in general terms and cfm ratings of ducting material. Believe me I use insualted flex and pull it tight and minimize direction changed for most of our bath fans. But I have used the pvc before too. Some of our bigger fans require 6" ducting, and flex was used to minimze fittings.
 
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