How do we keep our church/nave/sanctuary/temple piano better in tune for longer periods of time?

Real question from a church I tune for twice a year: "Our building & grounds committee is talking with our architect about design. I mentioned that the piano goes out of tune when the temperature rises or falls sharply.

Is there an optimal temperature range to stay within? They’re thinking for all the time the room is in use—to keep it comfortable it’s like $2200/mo. 

Also, do you recommend a humidifier or dehumidifier?"

This is a difficult question to answer for a variety of reasons. But in short, pianos prefer around 42% relative humidity (RH) and a 'safe range' is between 35% and 55%. Fluctuating temperatures have a direct impact on humidity.

• If you keep the temperature in the sanctuary steady, the HVAC cost far exceeds what it would cost to tune the piano more often

• And, it’s not great for the environment :-)

• All churches that I tune for have this same problem; the sanctuary piano just doesn’t stay in tune for very long

• And yet there are budget concerns and competing priorities

• Some churches keep the temperature steady but I don’t know what range they use

• Some tune the piano more often

• Some just live with it being out of tune most of the time

• Some tune twice a year before Palm Sunday and Christmas

• Some tune 3 x year which includes summer

• Some tune every time there is a concert or a recital or special event / holiday

• I have occasionally suggested that if the piano is used for a wedding, that the church have the couple pay for a tuning just before the ceremony. I usually get a frown with this suggestion so it's not a popular solution

Suggestions:

• A climate control system might help but only a little, unless you also install a string cover, an undercover, and a piano cover that goes to the floor. Also, the piano has to stay plugged in and watered which is almost impossible for most churches. (It seems that a shared responsibility leads to forgetfulness.) When the piano gets moved, it gets unplugged and forgotten. Or the cord is run over and broken. The climate control system has a huge room to compete with so it works better if you keep the climate controlled around the piano, as noted with the covers.

• Tune the piano more frequently such as 4 - 6 x a year. Perhaps negotiate an annual contract to save on expense.

• Next time the HVAC is updated, look into humidity control for the room or the building