Seasonal Changes: Why Your Piano Seems to Fall Out of Tune Suddenly

Every spring and fall, my phone starts ringing a little more. The story is almost always the same: "It sounded fine last week, and now something's off." You're not imagining it. Your piano really did go out of tune — and it happened because your house changed around it.

Here's what's going on. All winter long, your furnace has been running. That forced air dries out your home, and your piano adjusts to that dry environment. The soundboard — that big sheet of spruce inside the piano — flattens out slightly as it loses moisture. The strings lose a bit of tension. Everything settles into a dry-winter equilibrium. 

Then March and April roll around. You turn off the heat. You crack the windows. The Pacific Northwest air comes in, and it's damp. The soundboard absorbs that moisture and swells. String tension shifts. And suddenly, the piano that sounded perfectly fine in January sounds sour.

This isn't a sign that something is wrong with your piano. It's actually a sign that your piano is doing exactly what it's supposed to do — responding to its environment. Wood moves with humidity. That's what wood does. The problem is that it doesn't all move at the same rate, so the tuning drifts unevenly. Some notes go sharp, some go flat, and chords that sounded clean start to wobble.

This is why, ideally, pianos are tuned every 6 months. Because your piano has been through a lot as the seasons have changed, even if it's just been sitting quietly in your living room.