How much humidity in the house?

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stumpy75

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Ok, now that it's gotten cold and dry outside, it's really drying out inside. Since I have some musical instruments in the house, I try to keep the humidity around 45-50%. At that point, the windows are just showing a little bit of condensation.

I have several humidifiers, and am using about 5-7 gallons a day to keep it at that level. I'm checking the humidity with a sling psychrometer, as most of the humidity meters are a joke...

So where do you keep the humidity at, and how much water/day do you use?
 
How much mold do you have growing in there?

http://rossandwitmer.com/blog/what-should-the-humidity-be-in-my-house


In general, indoor humidity levels between 35 and 45 percent are considered acceptable, but when asking the question "What should the humidity be in my house?," it's important to take into account the season. If your home is 70 degrees inside and the temperature outside is under 20-40 degrees, you should keep the humidity under 40 percent. For each 10-degree reduction in the outside temperature below 20 degrees, the maximum humidity level inside should decrease by 5 percent.

This is a good rule of thumb. It will also help prevent premature window failure if you have wood windows.
 
So where do you keep the humidity at, and how much water/day do you use?

No idea on humidity level, but when the stove is going there is a pan of water on top. Probably go through about 2 gallons in a day with the fire roaring.
 
We keep small, disposable, aluminum bread pans sitting inside the heat registers... the warm air from the wood furnace blowing across will suck them dry twice a day when it cold outside.
But 5-7 gallons a day sounds like an awful lot... on the worst day we might use 3 gallon... maybe.
We don't use any sort of "meter"... we use the dry throat/dry nose test... if out throats or noses feel dry, we add another pan to another heat register (shrug)
*
 
40 percent and outside temp is 30, no humidifiers going. We tried running a humidifier one year and did not seem to make much difference in how we felt so we do not bother.
 
How much mold do you have growing in there?

http://rossandwitmer.com/blog/what-should-the-humidity-be-in-my-house


In general, indoor humidity levels between 35 and 45 percent are considered acceptable, but when asking the question "What should the humidity be in my house?," it's important to take into account the season. If your home is 70 degrees inside and the temperature outside is under 20-40 degrees, you should keep the humidity under 40 percent. For each 10-degree reduction in the outside temperature below 20 degrees, the maximum humidity level inside should decrease by 5 percent.

This is a good rule of thumb. It will also help prevent premature window failure if you have wood windows.


Actually, I've been doing this for about 10 years, and have not found any mold. Although I have an old house, I have insulated, sealed and caulked every place I can think of. I have triple pane vinyl windows. I have really looked to make sure I do not have mold/mildew growing anywhere, and have not found it...even when I remodeled and opened the walls.

But, when it's 10 degrees and 40% humidity outside, and you bring that air inside and heat it to 70, the relative humidity drops to ~10% or less. That's close to desert conditions! I may be trying to keep a little more humidity than the recommended 35-40% though. I have also tried the dry nose tests, as well as when I start getting pokes of static electricity. When those things happen though, the inside humidity is usually ~25% or less, and that's not a good thing for me or the instruments... I do use humidifiers in the instrument cases to keep the humidity up around them.

I don't understand why do you reduce the humidity inside the house when the outside temperature drops? Humidity levels of 35-50% do make 70 degree temperatures feel warmer (at least to me). Why would you not keep the inside humidity the same, no matter what the outside temperature? Is it because of condensation on the windows and possibly the cold corners and walls that could foster mold/mildew?

In the link above, it states that "For each 10-degree reduction in the outside temperature below 20 degrees, the maximum humidity level inside should decrease by 5 percent." In a few days, it's supposed to be around -10F. That would mean a humidity level of around 25%, and that will bring on the dry nose and pokes... Those are unusual temperatures for this area, and it's interesting to hear what people in colder climate than I have here do.

One thing that might be different in my case is that it's just me here, and I don't generate as much humidity as a family would in a house... And, at 45-50%, my windows are just starting to show condensation when the outside temps are around 15-20 degrees.

Thanks for the replies so far! :)
 
I have a drafty old house and I struggle to keep it above 25% humidity. I can tell when it drops under 20 because I get shocked every time I touch a door handle. There's a pot on the stove that goes through 2-4 gallons per day depending on how hard I'm burning. I run mist humidifiers in the bedroom at night

Any instruments I care about I keep in a case with a humidifier. I have some clunkers that I leave out and they show no signs of suffering from the low humidity. On the plus side chips, crackers and cookies never get stale.
 
I have a drafty old house and I struggle to keep it above 25% humidity. I can tell when it drops under 20 because I get shocked every time I touch a door handle. There's a pot on the stove that goes through 2-4 gallons per day depending on how hard I'm burning. I run mist humidifiers in the bedroom at night

Any instruments I care about I keep in a case with a humidifier. I have some clunkers that I leave out and they show no signs of suffering from the low humidity. On the plus side chips, crackers and cookies never get stale.

Yes, I keep humidifiers in all the instrument cases too. That includes 5 guitars, a few banjos, and a mandolin or two. I have a wall hanger guitar that I keep handy when I want to pick something up and doddle a little, and it has not had any problems so far... However, maybe that's because I don't let the humidity get to arid levels in the house.

I'm guessing that the recommendations to lower the inside humidity levels in the house when the outside temperature drops is to keep the condensation on walls and windows down. But most articles I have found just talk about what is recommended and not why...
 
There was a study that showed that the more humidity (to a point), the lower the survival of viruses inside a house during winter. Obviously there is a turning point where mold starts to grow.
 
I'm running a ventless gas heater downstairs in addition to the gas furnace. RH never drops below 35% and I use a sling psychrometer as well as digital meters. The psychrometer always reads a little higher RH. I've read that older guitars are not affected as much by low RH as newer guitars - anyone else hear that?
You could also put a hot tub inside, RH stays around 55% on the coldest days and it feels soooooo good!
 
Yes, I keep humidifiers in all the instrument cases too. That includes 5 guitars, a few banjos, and a mandolin or two. I have a wall hanger guitar that I keep handy when I want to pick something up and doddle a little, and it has not had any problems so far... However, maybe that's because I don't let the humidity get to arid levels in the house.

I'm guessing that the recommendations to lower the inside humidity levels in the house when the outside temperature drops is to keep the condensation on walls and windows down. But most articles I have found just talk about what is recommended and not why...

In walls, attics, etc... lot of areas not easily seen.
 
I'm running a ventless gas heater downstairs in addition to the gas furnace. RH never drops below 35% and I use a sling psychrometer as well as digital meters. The psychrometer always reads a little higher RH. I've read that older guitars are not affected as much by low RH as newer guitars - anyone else hear that?
You could also put a hot tub inside, RH stays around 55% on the coldest days and it feels soooooo good!

The ventless gas heater will put humidity into the air, so that's helping some... My digital humidity meters are both higher and lower than the sling psychrometer, and even two meters of the same brand can't agree even with each other.

I have not heard the thing about newer vs older guitars, and since all of mine are old, I have nothing to compare. :guitar:
The hot tub idea sounds nice, but I don't really have a spot for it. It does sound nice though! :havingarest:


In walls, attics, etc... lot of areas not easily seen.

I do agree with that, but so far, even when I've had the walls open in the kitchen and bathroom, I have not seen a problem. Possibly I'm just pushing my luck...

There was a study that showed that the more humidity (to a point), the lower the survival of viruses inside a house during winter. Obviously there is a turning point where mold starts to grow.

Interesting!
 
The ventless gas heater will put humidity into the air, so that's helping some... My digital humidity meters are both higher and lower than the sling psychrometer, and even two meters of the same brand can't agree even with each other.

I have not heard the thing about newer vs older guitars, and since all of mine are old, I have nothing to compare. :guitar:
The hot tub idea sounds nice, but I don't really have a spot for it. It does sound nice though! :havingarest:




I do agree with that, but so far, even when I've had the walls open in the kitchen and bathroom, I have not seen a problem. Possibly I'm just pushing my luck...



Interesting!

It's more an issue in a newer "sealed" house. The picture I posted is a chart adapted from a study from the University of Minnesota about indoor air quality in winter.
 
Been cold here, seen zero a couple mornings . I seen upper 50 humidity when warmer , about 30 out . Running in the low 40 now, being colder no water pan on the stove , The fox fire or shelter this would not happen . Not sure how the drolet puts humidity in the house ? A tight house will kept will kept humidity level better , most of the drying an cracking of the skin , comes from showering or bathing in to much hot water , or lack of cold water . Not just your skin pays this price , most health problems start here .
 
20%-30%. Lots of static electricity but I spend all summer taking water out of the air in the house, not about to spend all winter putting it back in so long as there are no nosebleeds etc. in the house.
 
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