Recommended Humidity Level?

[Mr. Zipper]

I bought some industrial shelving and started on my comic room in my new home this past weekend. The comic room is in the basement which is half finished at this point.

 

It's fairly dry down there, but I bought a de-humidifier just to be safe. What should I set the de-humidifier at.... what's the recommended humidity level for comics?

 

[lighthouse]

Stable humidity is more important than how low it is. Any number in the 30-40% range will be doing your comics a great service, but you would be better to have them at 45% all the time as opposed to 30% some of the time and 60% some of the time. So I would set it as low as you think you can keep it constant.

 

I have (no lie) thirteen humidity gauges in the areas where I store comics. About half of them are the cheap plastic analog ones that Sunbeam makes, which are getting harder to find (probably because the only cost about $7). The others are digital thermometers with humidity gauges, mostly from GE (mostly in the $15-20 range)...

 

Do NOT trust the gauge on your dehumidifier. I would strongly recommend purchasing at least two others (cheap ones are fine) and put them in the same room in different areas. I always hang one off the corner of the shelving right up against the comics. The gauges are very slow to respond to changes. It will take a minimum of 6 hours and usually around 36 hours before you will see readings you can trust. If you haven't already turned on the dehumidifier I would wait a day or two and get a real reading on the room first.

 

If you haven't moved your comics into the new room yet, I would recommend getting a humidity reading from the place where they are currently stored as well. If the difference is less than 10% you can move them at any time. But it's a VERY bad idea to move comics between locations with a dramatic change in humidity. Sudden changes in humidity will warp newer comics and can leave those "high-water" marks on older newsprint books. As a rule of thumb, I would give them a week for every 10% change you need to make. So it may turn out that you need to leave them resting in the new location for a week before you turn your dehumidifier on.

 

Let us know how it works out.

'House

[fantastic_four]

If Long Island humidity in the summer is anything like the humidity here in Virginia, 45 to 50 percent humidity is about the best you can do. The reason for this is that unless you have an air conditioner in the room with the dehumidifier, the dehumidifier itself will raise the temperature to 80 degrees or more if you keep it running high enough to push the relative humidity to lower than 45 to 50 percent.

 

You might be able to do better than I have since you're using your basement...I'd shoot for 40 percent humidity plus or minus 5% if I were you.

[underthebigw]

Ditto what Lighthouse sez. A few additions--buy a sling hygrometer. They are infinitely more accurate than digital ones, and only take a second or two to use. They can be found for about $125. I wouldn't use it all of the time, but they are extremely useful to establish a baseline and determine how accurate the digital ones are.

 

ALso, don't put the shelves against the walls. Not only does this allow insects to make it onto the shelves, but it inhibits air flow and allows micro-environments to be established ( in this case, possible pockets of humidity).

 

As for the dehumidifiers, don't count on them to work at all times. Most don't work during the winter, when basement temps. dip below 60 degrees, and humidity rises because of the cold (remember, cold air is more easily saturated-or, I should say, the same amount of moisure in cold air will result in higher RH's). In addition, most dehumidifiers don't work when the RH is at 50% or lower, so getting to the ideal level is problematic. Finally, (Donut will laugh at this), clean the dehumidiers regularly, especially if they don't have a dust filter. The coils collect dust and mold spores, and the latter will start to germinate in the moist environment of the coils and the bucket. It's best to have a continuous flow to a drain.

 

Since you're putting your books in the basement, here's another tip I learned. Use double-sided carpet tape around your shelves to establish a sticky perimeter that insects trying to lunch on your books will get stuck on. It's not only preventative, but helps you monitor what's in your basement. In fact, my best advice on shelving is to buy the metal wire units that you can now get inexpensively at Home Depot-incredibly strong, allow good air flow around boxes, and you can put the carpet tape around the individual legs. Works like a charm.

[Apotheosis]

Ok... since this topic was brought up... Is there such a thing as too little humidity? I live in Phoenix and it's about as dry as you can imagine here. I always figured that was a good thing as far as comics were concerned, but I'm open to the idea that you guys know a [!@#%^&^] load more about them then I do

[Mr. Zipper]

Thanks for the great advice guys!

 

One other thing I've done that I failed to mention earler is that I have placed one cedar block in each box and also put cedar on the shelves between the boxes. (I use magazine boxes so there is plenty of room to slide cedar blocks into the boxes) Will cedar repel insects other than moths?

 

[PedigreeMan]

Stable humidity is more important than how low it is. Any number in the 30-40% range will be doing your comics a great service, but you would be better to have them at 45% all the time as opposed to 30% some of the time and 60% some of the time. So I would set it as low as you think you can keep it constant.

 

Has there been any new research done indicating the benefits of storing paper in less than 50% humidity? My understanding all these years was that any stable value between 35% and 65% was fine, and that humidity problems only started to appear when the values approached 70% and above (mold growth and foxing) or 30% or below (early brittleness). Anyone run into problems with values between 50% and 60%?

 

Alan

[OldGuy]

Man, all this sounds complicated. Just move to Santa Fe and don't worry about it.

[blowout]

Man, all this sounds complicated.

 

[kahml]

Man, all this sounds complicated. Just move to Santa Fe and don't worry about it.

 

It is something Ricki (my SO) and I would love to do - just about any day!

 

Larry