Humidity Control

Registered Piano Technician



Why should I be concerned about humidity control for my piano?

Pianos, being built mostly out of wood and metal, are extremely vulnerable to changes in humidity.  Some of the problems that can arise due to changes in humidity are: 

  • String rusting and breakage - Metal parts, such as strings and tuning pins, can become rusty in times of high humidity, possibly resulting in string breakage and false sounding strings. 
  • Key and Action Problems - Wooden parts are vulnerable to both high and low humidity, because wood swells with high humidity, and contracts or shrinks with low humidity.  High humidity (such as we experience from about late June through September in West Michigan) can cause problems with wood parts, such as:  sluggish action response, sticking keys and poor repetition.  During periods of low humidity (such as we experience during the winter heating season in Michigan), action parts will become loose, and click and rattle.  Glue joints can fail, causing hammers and other parts to come loose. 
  • Damage to Pinblock, Soundboard and Bridges - High humidity can cause damage to pinblock, bridges and soundboard, as wood fibers are crushed due to swelling.  Low humidity can also cause significant problems with these components.   Tuning pins become loose as dryness causes the pinblock to shrink, and can result  in notes slipping grossly out of tune.  Cracks develop in the soundboard and bridges, and soundboard ribs can separate from the soundboard.  All of these problems can necessitate major and costly repairs. 
  • Tuning Instability - In addition to the damaging physical effects of humidity changes on a piano, another major consideration is the enormous effect of humidity changes on tuning stability.  In times of high humidity, the soundboard swells, raising the bridges and increasing tension on the strings, which causes the pitch to go sharp.  In times of low humidity, the soundboard contracts, letting the bridges drop, with a resulting decrease in string tension.  This causes the pitch to go flat.  The big problem is that different parts of the piano scale go flat or sharp in differing amounts.  The middle and upper treble sections can move a great deal, while the bass section will often move hardly at all.  The tenor section will usually move wildly flat or sharp.  This can create a horribly out of tune piano, sometimes in a matter of just a few days when the humidity changes significantly. 

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How can I protect my piano from changes in humidity?

A special humidity control system designed specifically for pianos is available from Wood Piano Service.

Called a Piano LifeSaver Humidity Control System from Dampp-Chaser Corporation, the entire unit fits inside an upright or under the soundboard of a grand. The system is totally silent, as it has no moving parts. It consists of a humidifier unit, dehumidifier unit, and a humidistat which detects the amount of moisture in the air and energizes whichever unit is needed. A flashing light alerts you when the water level gets low. The only maintenance involved is refilling the humidifier reservoir periodically (when the low water indicator light begins flashing) and replacing the humidifier evaporator pads once or twice a year, depending on water hardness and mineral content.

I always recommend that piano owners make every attempt to control humidity levels in homes and other settings.  The use of a humidifier, furnace mounted or room-type,  can help greatly to combat dryness in the winter.  However, in some situations, a humidifier is impractical, such as the large open areas in schools and churches.  Furthermore, a humidifier in the home does nothing for the opposite problem, high humidity, which we typically experience from June through September in Michigan.  This is another reason why the Dampp-Chaser humidity control system mounted in the piano is so effective.  Not only does it provide the piano with needed humidity during the winter heating season, it also works to dissipate excess humidity levels in the piano at other times of the year.  The system constantly monitors the situation in the piano, and automatically engages whichever side of the system is needed at any given moment, constantly working to maintain the optimum level of 42% relative humidity for the piano. 

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What are the benefits of humidity control for my piano?.

While not eliminating the need for regular piano maintenance, humidity control will allow more stable tunings by reducing the radical pitch changes your piano experiences through the seasons. When your piano stays closer to its correct pitch level of A440 (A-440 cycles per second), your technician does not have to perform a large pitch raising or lowering procedure prior to fine tuning. Thus, a balance of forces is maintained between the strings and the frame of the piano, allowing more accurate and stable tunings to be done.

In addition, a stable environment will help to preserve your piano through the years. Wood parts, glue joints and metal parts will all last longer if not subjected to excessive humidity swings. Maintaining the correct environment will preserve your piano investment for a lifetime of enjoyment.

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Major Piano manufacturers agree on the benefits of Dampp-Chaser:

    "Baldwin recommends the Dampp-Chaser system as a valuable means to help insure the longevity and stability of our pianos."

    "The usage of Dampp-Chaser humidity control systems effectively compensates climatic changes within the piano's environment and is for that reason beneficial in terms of stability and long term reliability."

    "Your Dampp-Chaser humidity control systems are the best and most carefully designed systems we have seen."

    "The best way to preserve the value of fine grands and uprights is to automatically regulate the relative humidity right within the instrument..with a System from Dampp-Chaser Corporation."
    --Nikolaus Schimmel

    Steinway & Sons
    "The installation of a Dampp-Chaser Humidity Control System can, in our opinion, provide a degree of climate control for the piano which may not be otherwise attainable."

    "...the proper installation and use of a Dampp-Chaser system can be beneficial to the stability of the instrument."

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What is the cost of the Piano LifeSaver system?

    Grand Pianos 6’ and under:  $625 installed

    Vertical Pianos:  $595 installed

    Grand Pianos over 6’:  $825 installed

  • Disklavier Vertical Pianos:  $749 installed

  • Since the Piano LifeSaver humidity control system by Dampp-Chaser must be installed by a qualified piano technician in order for the warranty to be in force, sales of the Piano LifeSaver system are not done over the internet or via this web site.  Consequently, I only sell and install these systems to customers in my own general service area.  To request more information regarding the system or installation:

E-mail us at

or call (231) 744-1969.

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