Bathroom exhaust make-up air and flow

[Zayd]

Hello, everyone. As I continue my basement finishing project, I am planning my bathroom fan location and am hoping to get some simple guidance on how feasible my approach is from an air movement standpoint.

I originally planned to place the bathroom exhaust fan in a conventional location near the shower and toilet. Ceiling height concerns have me evaluating alternatives. Foremost, I don't want to do anything that compromises the purpose of the exhaust. At the same time, if I can achieve an effective exhaust arrangement while saving whatever ceiling height I can, that's the goal. To be clear, I am not installing the fan within the joist bays above, but rather below them due to other equipment in the bays and direction of exhaust.

Option 1 is to accept the lower ceiling and keep the original placement, relying on make-up air coming in from the door gaps:




Option 2 involves moving the fan near the door, reducing the door gaps down to a minimum, and installing a louvered opening in the wall of the bathroom that pulls make-up air from a conditioned adjacent storage room. My rationale is that this new opening would pull from the shower and toilet direction and help move humid/stinky air to the exhaust:




Is this a sensible solution? Or am I rolling the dice on this working?

 

[Fitter30]

Would a ducted fan work ? Where the fan isn't in the same room.

https://www.amazon.com/dp/B09FYK6Z3R/ref=sspa_dk_detail_0?pd_rd_i=B09FYK6Z3R&pd_rd_w=I4xyg&content-id=amzn1.sym.386c274b-4bfe-4421-9052-a1a56db557ab&pf_rd_p=386c274b-4bfe-4421-9052-a1a56db557ab&pf_rd_r=0HBC7Y6Y33SJEMRXMR9V&pd_rd_wg=kM3uG&pd_rd_r=98a32ac8-596e-4037-90e4-e3c552f3cf28&s=lawn-garden&sp_csd=d2lkZ2V0TmFtZT1zcF9kZXRhaWxfdGhlbWF0aWM&th=1

https://www.amazon.com/calimaero-Adjustable-Ventilation-Inline-Exhaust/dp/B010JUJTZC/ref=asc_df_B010JUJTZC/?tag=hyprod-20&linkCode=df0&hvadid=343238709768&hvpos=&hvnetw=g&hvrand=16275336665525993527&hvpone=&hvptwo=&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=200619&hvtargid=pla-421263807091&psc=1&tag=&ref=&adgrpid=68770748373&hvpone=&hvptwo=&hvadid=343238709768&hvpos=&hvnetw=g&hvrand=16275336665525993527&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=200619&hvtargid=pla-421263807091

 

[Sponsor]

 

[John Gayewski]

Your plan should work if you have the makeup air hole large enough to favor that, rather than the door gap.

 

[Zayd]

Would a ducted fan work ? Where the fan isn't in the same room.

That would be ideal, but I have the same joist bay obstructions to deal with, so it won't save any headroom.

 

[Reach4]

Suppose you put sheet metal across the bottom of one joist bay, and that joist bay, free of electrical stuff, would be a plenum?

 

[Zayd]

Suppose you put sheet metal across the bottom of one joist bay, and that joist bay, free of electrical stuff, would be a plenum?

Great idea except that the joists run perpendicular to the two fan locations. Believe me, I've run through just about every permutation of what is possible. 9" is a lot to lose!

 

[Fitter30]

Could have some duct made 2"x12" = 24 sq inches

 

[WorthFlorida]

Exhaust fans can be wall mounted between the studs.

 

[Zayd]

The other complication I forgot to mention: I am mounting a Panasonic combination heater/fan, so the heat being close to the shower area is ideal. I am still willing to abandon this fan and remotely mount a fan with shallower ducting to the shower area, as suggested here. That leaves the heater portion to deal with, and perhaps an electric wall-mounted heater is the solution there.