How often does a piano need tuning?

A commonly-asked question is how often a piano should be tuned. The standard recommendation is every six months for a piano that is in a normal domestic environment, though some people choose to leave the piano for a longer period (a year or so). In a lot of cases, a piano left much longer than this will start to go quite noticeably out of tune.

New (or recently restrung) pianos will require very frequent tuning (every 3 months) for the first year or so - this is because the strings actually continue to stretch for a while after being installed on the piano and first brought up to pitch. After this, it should be fine to revert to a more normal tuning schedule.

What causes a piano to go out of tune?

The biggest single factor is changes in humidity, although temperature can also have an effect. The wooden parts of the piano will expand and contract very slightly as the relative humidity changes. In most centrally-heated homes, the humidity will decrease in the winter months because cold air is warmed up without adding any moisture to it, which makes the relative humidity drop, whilst in summer doors and windows are opened allowing in relatively moist air from outside.

Do all  pianos go out of tune at about the same rate?

Generally speaking, older pianos tend to go out of tune more quickly than newer ones because, over a period of time, the wrest plank (the piece of wood that holds the tuning pins) can dry out if the piano has been in a low-humidity environment and its grip on the pins will loosen. Additionally, newer pianos (post-1945) normally have wrest planks made of bonded cross-ply timber (rather like plywood) which is better able to resist the low-humidity conditions of modern central heating than the solid wood planks on older instruments.

Can a piano be "damaged" by not being tuned regularly?

The answer is no, simply not tuning a piano does not in and of itself cause harm to the piano or cause it deteriorate (though storing it in very damp, very dry or otherwise unsuitable conditions will). However, there are some significant disadvantages to leaving a piano untuned for a long period of time; gradually the pitch of the piano will drop and it is then a very much bigger job for a tuner to get it back into a good tuning condition (and on pitch) than if the piano has been kept regularly tuned (most tuners will quite reasonably charge more for this). Additionally, pianos can gain a stability from being tuned regularly which arises from the fact that the tuner doesn't have to move all the strings a long way every time, so if you habitually leave your piano for a very long while between each tuning, the stability may never be quite as good.

If a piano has been neglected for a very long while and fallen a very long way below pitch (such as a tone or a minor third), it might take several tunings to get it back to standard pitch if this is the desired option. With some older pianos, attempting to do this may be inadvisable. A piano technician will be able to advise on the best course of action depending on the age and condition of the instrument.