A consumer's question on humidity...

[ge7243]

Hello, I have absolutely no technical or professional experience with anything HVAC related, whatsoever.

That out of the way, in my family's house I have a number of acoustic musical instruments, some dating back to 60+ years in age. Of key importance to their longevity is the humidity of the ambient air.

I had taken note that a hot shower really raises the humidity within the bathroom quite a bit when the ventilation fan is not turned on, but I was told that when it is on, it simply exhausts all of that humid air outside the house.

I was wondering if it'd be ethical or plausible for a technician to reroute the ventilation duct to a room in the house (or possibly into the air vents themselves)? I've been told by my mother about how the humidity promotes the growth of mold, which is a reasonable concern considering she has to take care of the house, I just live in it. I just don't really like the thought of such a resource going to waste.

So, in the professional opinion of the users here, is this too much of a crack pot idea to even consider? Could any damage be done? As well, I'm wondering what any other options may be. I'm sure there's a better solution, this was just a major curiosity for me.

My apologies if anything I said was presumptuous, thank you for your time.

[badtlc]

Keep in mind what you consider a waste in the winter becomes a hindrance in the summer. You really need a whole house humidifier with a humidistat that maintains a proper humidity level in the house at all times.

[Gunnery Sergeant Hartman]

What happens when there's a rumble in the jungle and you drop a growler?

Do you just let the smell stay in the bathroom, or do you send it throughout the house?

[Shophound]

As Gunny said, it's not just bathroom humidity that would be exhausted into the house. It is against mechanical codes to tie exhaust into air conditioning/heating systems.

Since I work in a museum, I know a few things about creating environments favorable for preserving special objects. Humidity control is very important, followed by temperature. The less variance, the better. A bathroom exhaust ducted into the house, even if it was kosher to do so, would set up the guitar gallery for spikes and droops in humidity.

First thing to consider is why your indoor air is too dry. That's usually due to too much outdoor air leaking into the house during the winter, driving down indoor humidity. Weatherizing can slow this leakage...you don't want to outright stop it or your house air will become foul.
Next, consider a whole house humidifier. Set it to hold the house between 35-45% relative humidity...the colder the outdoor temperature is, the lower the humidity setting should be. This is to prevent condensation on your windows and possibly inside your walls and in the attic.
For summer cooling, be sure your a/c system can keep relative humidity below 55%, and you should be able to enjoy those guitars for many years into the future.

[beenthere]

Its also against code to vent the bathroom exhaust fan into another room.

Also think of the germs and bacteria you would spread through out the house when the fan was running and the toilet was flushed.

[dano]

You guy's are making me hungry!!

[gonekuku]

A 100 sq ft x 10 ft ceiling bathroom at 72F with 95% humidity can hold about .038 gallons of water in the air.

Mix this water vapor with the rest of a 900 sq ft home at 72F with 20% humidity(.30 gallons in the air), the resultant is 1000 sq ft at 21%.

To bring 1000 sq ft from 20% to 40% at 72F, .38 gallons are needed.

Keep in mind, you are always losing or gaining humidity through infiltration. Even with a stand alone humidifier, it's tough to keep up with the speed at which the water vapor is blowing in the wind through the cracks.

[ge7243]

Thanks for the replies guys, both on hearing how it's against code and how it wouldn't be too technically feasible at any rate. It does seem that our house is a bit drafty in places, that could probably use some looking into if just to kill two birds with one stone so to speak.

[Carnak]

Believe it or not their are products out there that you could call a "Guitar Humidor"

[DanW13]

It's called the guitar case and a cup of water with a sponge in it with a hunidity gauge.

[cem-bsee]

one more time: be careful in giving advise about OUTDOOR AMBIENT!

in Huntsville AL, our relative humidity is still high until 10am through-out the winter months!

most times greater than 70% even with OD temp of 30- 50F.

I sure do not want to draw in this water vapor into my house.

&
it seems to me that most items are 'comfortable' if their ambient is within the recommended range for humans = 35- 55% RH.