Why Do People Water Their Pianos?

What they're really talking about is the presence of a piano humidifier.

woman playing piano at home

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Question: I just inherited a baby grand piano from my great-aunt’s estate (I played for a few years back in elementary school and I guess she remembered). My boss was over last week eyeing the new addition to my living room and asked if I was planning on "watering my piano." I nodded my head and pretended I knew what he was talking about, but the truth is, I have no idea. My piano needs to be watered? Like I’m supposed to pour water over it? What exactly will that do except ruin my piano?

Answer: Pretending to know exactly what someone’s talking about when really you have no clue? I’ve done that many times. On one occasion in particular, I started to disrobe when my doctor asked to see my glabella, not realizing that my glabella is actually on my face. (OK, fine, maybe that didn’t happen, but it would make a good story if it did.)

So, do you have to pour a bucket of water on your piano once a week? No. As a matter of fact, please don’t. But what your boss was referring to as "watering your piano" is actually a phrase used to explain the presence of a piano humidifier. Yes, that baby grand in your living room is as divalicious as Mariah before a big concert. See, besides for the keys and the pedals, a piano is mostly made up of wood. Wood, like any living thing, is sensitive to the presence of water.

Too much water in the air can cause the wood pieces of your piano to swell. Too little water in the air can cause the wood to shrink, drastically changing the way your piano sounds and, in extreme conditions, causing your piano’s soundboard (a critical piece of the instrument) to warp and even crack. All of these factors mean that keeping the humidity in and around the piano stable is critical.

Ideally, the humidity in the room that houses your piano should be 45-60%, with the higher end being the better side to err on (that’s because dry air will cause more damage to your piano than humid air will). As a side note, keeping the humidity below 50% is also a good idea to prevent mold growth anywhere else in your home.

One way to do this is by installing the Piano Life Saver system that is essentially an interior humidifier for your piano. For several hundred dollars, you can have this system installed by a professional, and it constantly monitors and maintains the humidity inside your piano.

If you don’t want to invest in such an expensive system, you could simply pick up a hygrometer from your local hardware store to measure the humidity levels around your piano. Keep in mind that it will likely be different in the winter than in the summer months. Then, based on your findings, you can purchase an external room humidifier to regulate the humidity around your piano. It’s definitely a cheaper option than the Life Saver system, but also less accurate.

My friend Rachel, a homeowner in Ocean County, N.J., is happy with the purchase of her Life Saver system for the piano she inherited from her parents. "I know that this family heirloom is going to continue to be in our family for years to come, because it’s getting the exact right amount of moisture all the time, no matter what the season, no matter what the temperature in my house," she explained. "Hopefully this piano will be something I pass down to my grandchildren."

No matter what you choose, it’s important to have that piano looked at by a professional piano tuner to give you a better idea of your needs. Your great-aunt would hate to see her piano ruined by your carelessness (that’s just a guess here). And next time your boss comes over, you can look him in the eye with confidence knowing exactly what he’s talking about.