By Eathan Janney, Founder — Floating Piano Factory
Piano owners in Chicago tend to notice something is wrong before they can name it. The keys feel heavier in July. The piano sounds thin and flat by February. A note sticks, or a pedal suddenly squeaks. These aren’t random events — they’re the predictable result of Chicago’s climate working on your instrument, season after season.
Understanding what’s happening, and why, is the first step toward stopping it.
Chicago’s Climate Is Unusually Hard on Pianos
Most cities have seasonal humidity variation. Chicago’s is extreme.
Indoor relative humidity in a Chicago home during January and February — with forced-air heat running — often drops to 15–25%. By July, the same room can reach 65–75% on a humid summer stretch. That’s a swing of 50 percentage points or more, and your piano’s wooden structure responds to every point of it.
Piano manufacturers design instruments for a 45–55% relative humidity range. Chicago spends most of the year outside that range.
Three Parts of Your Piano That Take the Damage
1. The Soundboard
The soundboard is the spruce panel beneath the strings that projects your piano’s voice. It has a slight upward curve — called crown — built in at the factory. That crown is essential to tone.
In winter: Dry heat pulls moisture out of the soundboard. It contracts, flattening the crown. Strings loosen, pitch falls. Sustained low humidity — weeks below 20% — eventually causes the board to crack. Soundboard cracks are among the most serious structural problems a piano can develop.
In summer: Humidity swells the board upward, tightening the strings. Pitch rises. Tone becomes compressed and overly bright.
Repeated cycles of swelling and contraction weaken glue joints, stress the bridge, and gradually accelerate deterioration. A well-cared-for soundboard can last the lifetime of the instrument. One that’s been through decades of Chicago winters without humidity management may need serious work by the time it shows visible damage.
2. The Action
The mechanical action — hammers, shanks, wippens, flanges, jacks, and the felt components that connect them — is where physics meets music. It’s also almost entirely made of wood and felt, which means it reacts to humidity in ways players feel directly under their fingers.
When humidity rises: Wooden action parts swell. Felt compresses. Key bushings tighten around their guide pins. The result is a heavier, more resistant touch — sometimes noticeably different from one week to the next.
When humidity falls: Felt shrinks. Regulation clearances shift. Keys that were evenly weighted become inconsistent. Repetition becomes less reliable. Players often describe this as the piano “not responding the way it usually does.”
Over time, these cycles cause the felt to lose its resilience, accelerate wear on wooden parts, and require more frequent regulation to maintain a consistent touch.
3. The Strings
Steel piano strings are vulnerable to humidity in a more direct way: moisture causes rust.
In Chicago summers, prolonged elevated humidity — especially in a basement, near an exterior wall, or in a room that warms and cools significantly overnight — can promote surface oxidation on the steel strings. Rust dulls tone, creates surface roughness that affects string-to-hammer contact, and shortens string life. Bass strings, which are wound with copper, are somewhat more protected, but treble strings are exposed and vulnerable.
Cold, dry winters are less damaging to the strings themselves but create secondary risk: a soundboard that contracts and glue that loosens can shift bridge pins, affecting how strings seat at the contact point.
What Proper Care Looks Like
Humidity management is the highest-impact thing you can do. A room humidifier set to maintain 45–50% relative humidity in winter prevents the most damaging seasonal swings. Pair it with a hygrometer — the humidifier’s built-in gauge is often inaccurate.
For instruments in rooms with inconsistent HVAC or variable use, a Piano Life Saver system (installed inside the piano) maintains stable humidity at the soundboard level regardless of room conditions. It’s a worthwhile investment for any quality instrument.
Piano placement matters more than most owners realize. Avoid exterior walls, heating vents, fireplaces, and south- or west-facing windows. An interior wall, away from direct HVAC airflow, provides the most stable environment.
Regular tuning catches problems early. In Chicago’s climate, twice-yearly tuning — once in late fall, once in late spring — keeps the piano in a playable range and gives a technician the opportunity to flag humidity-related issues before they become structural ones.
Book Chicago Piano Service
If your piano has been through Chicago winters without humidity management, or if you’re noticing any of the symptoms described here, a professional evaluation is worth the time.
Book a Chicago tuning or care consultation →
Floating Piano Factory offers individual tunings, comprehensive piano care visits, and Piano Care Memberships for clients who want year-round protection and priority scheduling. Reach out to learn what’s right for your instrument.
Eathan Janney has been tuning and caring for pianos professionally since around 2000. He serves clients throughout Chicago, New York, and beyond.