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V, the Despotic Quibbler

My Homemade Personal Humidifier

Dry is badI live in a house where during winter times it gets desert-like dry, humidity level drops to as low as 14% while outside it is a nice 45% or more. Blame the furnace for burning all the humidity out of our house's air! My health suffers, my family health suffers, furniture, piano, floor, anything that is made of wood suffers, not to mention those wicked static shocks!

We do have a whole-house humidifier but it does not reach the upstairs floor that is served by an independent heat pump installed in the attic where we can't have a humidifier, so I decided to assemble a homemade device, just to make my office, where I spend lots of time, more comfortable.

First you will need to buy or gather some material and then you can start building it. Click the small white arrow to your right and follow the steps to make your own personal humidifier.

bucket

You'll need a nice and wide blue :-) bucket. This is a 6 gal. bucket bought at Home Depot for $20. A low profile drain pan can also work since, after some experiments, I found out that there will be no need to have water inside the bucket (which was my original idea), it is used as a precaution only.

space heater

You'll need a space heater. You can use a fan, instead. I already had the heater to warm up my office, so now it performs a double duty, to heat and to help humidify. Cost of one new is around $99. A fan would cost much less but would also be less effective in producing humidity.

bath rug

Have a nice, blue :-) and fluffy bath rug. Along with the bucket, it will serve only to protect the floor (that, in my case, is wood) from water spills, drops and, ultimately, any kind of unforseeable damage. I love my floor so I need to protect it!

box

A box should help keep the space heater at the right height. This one was an Ikea wine box that my wife wanted me to throw away long ago and I refused. Now, it serves a good purpose.

stool

A comfortable stool so you can rest while you provide water to the humidifier. This is an optional item of the setup :-).

hand sprayer

You will need a hand sprayer. I bought this one that has a 1.75-liter (4-pint) capacity. It is a perfect size, not small, not big and works very well. It also has a nozzle that I can adjust to have the right kind of spray, not too wide, not too narrow. Paid $7 at Home Depot.

energy consumption

You can make good use of a Kill-A-Watt ($20), a little instrument to measure how much energy a device is using. Since I am using a space heater that can use up to 1500W, I like to set its thermostat based on its energy consumption to avoid a "surpreese" when the energy bill arrives.

extension cord

A power cord extension gives you freedom to place your homemade humidifier wherever you want and, most importantly, it will allow the Kill-A-Watt to be where it can be seen.

grip liner

My heater may make a bassy humming sound that is amplified by the wood in the floor and in the box so I use some thick grip liner to isolate the heater from them and it seems to do the trick of making it more silent.

power switch

My heater has a weak spot, its on-off power button. It is failing! So, I leave it always on and use a stand-alone switch ($10) to turn it on and off now. It is a great space heater but unfortunately it suffers from this problem. I have a second space heater, same brand, same model, same problem.

towel

This is important! The towel you will use. You need a towel that can retain water. Some towels will drip water too easily and fast once wet and hung. Some will not. It can be old, it can be ugly, but it needs to be a good water retainer! If possible, blue :-). And you will need at least a couple of them.

PVC cutter

For the construction of the rack (next step), I highly recommend that you use a PVC pipe cutter. It makes clean and straight cuts in PVC pipes. Home Depot sells this one for $30.

PVC rack

Here is where you show your skills. Build a rack like this made of PVC40 pipe. One 3/4" x 10' pipe ($5) is enough. 4 tees ($2), 6 caps ($2) and some cutting will do. The PVC cutter (previous picture) is handy. No need to use primer and cement. Just use pressure when connecting the pieces. It will hold. Mine did.

Clothes hanger

You will need a small water-proof clothes hanger. This one again my wife wanted me to throw away, it came as a "bonus" in some clothing bought for my daughters. Again, I saved it and now I found a use for it.

Hygrometer

Essential. An accurate hygrometer so you can know when the humidity has reached the desired level. Mine is analog and very accurate. Does not obviously use battery. But there are some very good electronic humidity monitors out there too (e.g., AcuRite 613, $10).

Temperature monitor

Optional. Since I'll be using a space heater as the air blower for my humidity apparatus, I need to be aware ot the temperature in my office. I've learned that I can't trust my body to warn me when it is getting too hot because I just like hot rooms. I need a temperature monitor to tell me when to turn the heat off.

All material needed

You have now all the needed material to start assembling your personal homemade humidifier. So let's continue!

Step 1 of build

Place the rug on a flat surface of the most unused corner of your room. Place the bucket on top of it. Place the PVC rack inside the bucket.

Step 2 of build

Place the box aligned with the bucket. Place the space heater on top of the box. Place the small hanger in the rack, near the heater.

Step 3 of build

Plug the extension cord to the wall outlet. Plug the Kill-A-Watt to its other end. Plug the power switch to the Kill-A-Watt. Finally, plug the space heater power cord to the switch. Place the grip liners underneath the box and the heater to isolate any possible low-frequency noise.

Step 4 of build

Now, final step, place the towel on top of the rack making sure one end rests on top of the hanger, so that there is an opening near the space heater. The idea is that the air coming from the heater (or a fan) would enter through this opening and be funneled until it exits through the narrower other end.

Step 5 of build

The device is ready. Fill the sprayer with clean tap water. Now seat on the stool, grab the sprayer and spray water all over the towel, on both sides. Turn on the heater, with or without warm air (as a heater or as a mere fan), and watch your room's humidity level slowly improve. Enjoy a healthy 40% humid air.

A few extra tips:

  • When spraying water in the towel, do not overspray. Ideally, no water should drip through the towel into the bucket. A good towel is capable of retaining a fair amount of water. A low quality towel, made of cheap cotton or no cotton, will drip easily, which is not good. Do not spray the very bottom of the towel, leave a 3"-high "safety zone" at its bottom dry; it may eventually get wet by itself.
  • If your room was too dry for some time, the first days will require you to spray water much more often, because not only the air is dry but all things that absorb humidity in your room are also dry and will take the water from the air until they reach stability. Once you have a stabilized room, you will notice that the required water to maintain the desired humidity level is less.

A few extra tips (continued):

  • Do not pour water inside the bucket. My experience is that counting on the wicking effect of the water is far from enough to keep the room humid. You need the whole area of the towel wet to produce enough humidity. The wicking effect is not strong enough to beat gravity and take the water all the way up the towel to the top of the rack. Better just use the spray.
  • Another good reason to keep the bucket dry, most of the time, is that you need to avoid still water. Still water creates bad smell. For the same reason, try to only spray the towel after it has dried up completely from the previous time. Do not keep the towel wet all the time, this will allow mold and mildew to grow in the towel with bad consequences to your health and bad smell in your room.

A few extra tips (continued):

  • Change the towel every now and then or when you think it is smelling bad. I am able to keep mine for days without changing it because I allow it to dry whenever possible by not spraying water in it until it has been dry for some time (one hour at least, for instance).
  • If you blow warm air into the towel, it will dry the towel much faster and consequently, it will create humidity faster too. If you blow room-temperature air, it will take longer to dry the towel, hence producing less humidity. If you don't blow any air and let it dry naturally, it will still create humidity but at a much slower pace. This is what I do for maintenance of the humidity level at night, when I go to sleep. But once you have a stabilized room, you may not even need to leave it wet during nighttime.

A few extra tips (continued):

  • If you think about this homemade humidifier, it may look like a stupid thing to do and probably is. With less than $100 bucks, you can buy a good evaporative humidifier and not worry about anything but to keep its tanks full of water and perform the due maintenance.
  • Some advantages of my homemade humidifier are: it requires much less cleaning than a store-bought evaporative humidifier since it never has a tank full of water and water is always only in contact with the towel that is easy to replace for a clean one; it can also warm your room since I use a space heater to blow air into the towel. My house is dry only during the winter so I do need a space heater in my office. The more humid the air is, the colder it feels at the same temperature!

A few extra tips (continued):

  • Do not use ultrasonic humidifiers. They release the minerals from the tap water into the air and these minerals create a horrible white thin layer of dust in all surfaces they touch. Use evaporative humidifiers, they don't have this extremely annoying drawback, are much simpler to maintain and provide a healthier humidity to the air.
  • Do not let the humidity of the room go too high. High levels of humidity is as bad to your health and to the house as low levels. If you see condensation of water in your windows, it means you need to lower the humidity. This condensation, with time, can rot your windows or the window sill. A little bit of condensation may not be a problem though, you need to find the right balance. The literature recommends 30% to 50% humidity in winter times.

A few extra tips (continued):

  • Another extreme step that I took and that may not be suitable to most normal house setups was to totally shut down the only air ceiling register that feeds warm air from the heat pump to my office. The problem is that the air coming out from the heat pump is too dry because the heat pump, in the process of heating the air, literally burns the water from it. So I closed it! But now I have to use the space heater as my only source of heat to warm up the office. The space heater also burns humidity from the air but since it will be blowing warm air into the wet towel, it will be actually raising the humidity the fastest way. Using pure electricity to heat a room, which is what the space heater does, is not good since it is the most expensive way to heat a house but I decided that making my office comfortably humid is more important than saving money.

A few extra tips (continued):

  • Keep the door to your room closed at all times! If you leave it open, considering that the adjacent rooms will be certainly drier, your nice humid air will escape much faster than this humble homemade humidifier can make up for it. Educate your family members to not leave your door open: this may prove to be a very tough task though :-).

That's all for now. Be happy, have a healthy breathing!

Air quality
Tutorial is done