[Captflx]

I have determined the CFM exhaust I need for my bath to be 80; however with almost all baths, privacy with a closed door reduces the amount of airflow into the bath. My 24" door has a 1" opening at the bottom for airflow. I don't know how much air CFM this allows into the bath nor what the consequences are for my bath motor if this is insufficient.
Should I be concerned with this restricted air flow into the bath?

 

[Bondo]

I have determined the CFM exhaust I need for my bath to be 80; however with almost all baths, privacy with a closed door reduces the amount of airflow into the bath. My 24" door has a 1" opening at the bottom for airflow. I don't know how much air CFM this allows into the bath nor what the consequences are for my bath motor if this is insufficient.
Should I be concerned with this restricted air flow into the bath?

Ayuh,... That's 24 sq. inches....

How much air ya gonna push through a 4" flex-vent tube,..??

 

[hand drive]

spaces under doors are 5/8" up to over an inch average. as long as it is at least 5/8" off the floor the a/c-heat unit and bath fan will work just fine.

 

[federer]

yea you will be ok. i will be more concerened with the length of the duct run

 

[ddawg16]

I think you must add a small decorated window (A very small one) to your door so that air can pass through it properly but make sure you don"t see on the other side from any position and like wise.

Do what? I don't believe that is any code I have seen.

 

[md2lgyk]

Do what? I don't believe that is any code I have seen.

Never heard of it either. Nor have I ever seen a bathroom door with a window in it.

 

[gwilkrrs]

how did you determint the required cfm?

 

[md2lgyk]

how did you determint the required cfm?

By the size of the room.

 

[ddawg16]

how did you determint the required cfm?

Suggested CFM for the bathroom is based on cycling all the air in the bathroom 8 times per hour. The bath fan calculator is standard guide to help you find the minimum fan rating for your specific bathroom. The higher the bath fan rating the more air can be vented out of the bathroom, which means less moisture and mold build-up.

One of many web sites for calculating the cfm...

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

 

[RobertoAguiar]

One of many web sites for calculating the cfm...

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

Wow thank you very nice link, very helpful information.:thumbup:

 

[Captflx]

bath exhust

Thanks to all for the info.

 

[Windows on Wash]

One of many web sites for calculating the cfm...

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

Bookmarking that one.

Nice link.

 

[Gary in WA]

I'll stick with mine; flex duct, elbows, and roof/wall cap deductions; http://www.efi.org/factoids/bathroom_sizing.html

Lol.
Gary
PS. Termination hoods/fittings also create back pressure; from my dryer links; http://www.youtube.com/watch?v=cFOHGVhmyQA