How changing weather affects your piano’s tuning (and what you can do about it)

Cape Town is famous for its unpredictable weather. One moment it’s blazing sunshine, the next it’s a chilly breeze or a sudden mist rolling in. While this keeps life interesting, it also means that delicate instruments like pianos are constantly adjusting behind the scenes.

If your piano has started sounding a little off recently, you’re not imagining it. Weather changes, especially shifts in temperature and humidity, genuinely affect how your piano sounds. In fact, it’s one of the most common reasons pianos go out of tune.

So what’s really going on?

Pianos are made of natural materials like wood, felt, and steel strings, all of which react to the climate. The soundboard, which is essentially the voice box of the piano, is particularly sensitive to moisture. When the air is humid, as it often is in Cape Town summers, the wood swells and pushes on the strings. That tension makes the pitch go sharp. In winter, especially when it’s dry indoors due to heaters, the wood contracts and the strings loosen, making the piano sound a little flat.

And in a city where you can experience several seasons in one day, it’s no surprise your piano might struggle to stay in tune.

What can you do about it?

The easiest and most effective step is regular tuning. Twice a year is ideal, once around the start of winter and again when the weather begins to warm up. This helps your piano adapt to each season and keeps it in better long-term condition.

It’s also worth managing the humidity in your home. In drier months, a room humidifier helps maintain moisture in the air. During humid months, especially if you’re near the coast, a dehumidifier might be useful. Keeping your piano away from direct sun, heaters, and open windows also helps create a more stable environment.

If your child is learning to play, this is even more important. Young ears are still developing a sense of pitch. Practising on an out-of-tune piano can confuse that sense and make lessons less rewarding. A well-tuned instrument helps build their confidence and musical ear.

So the next time Cape Town’s skies swing from sun to storm in an hour, spare a thought for your piano. A bit of care and timely tuning will keep it sounding beautiful, no matter what the weather brings.