Piano World Home Page Forums Our Most Popular Forums Piano Tuner-Technicians Forum Humidity from leaking roof

My house has recently developed a roofleak. Living here in the deep south the humidity is high to begin with. We have had a lot or rain over the past two weeks so you can feel the rise in humidity in my home as the tempratures soars into the mid to upper 90%'s. I am working to solve the leak problem. I just purchased a slighly used Vogel Piano and it was delivered about a week ago. It has developed a lot of notes that won't play unless repeatedly struck and has gone badly out of tune. Do you think that theres been any damage done to the piano?? if not, what do you think it will take to fix the notes and what will is cost me?

Tommy

You need to call a piano technician. We cannot tell what is wrong with the piano over the internet, and we cannot set prices for others even if we could diagnose your problems.

Tommy!

You need to get the roof fixed, and you need to get the piano into a drier place...even if it means moving it out of your house until you get that roof fixed. Seriously.

All the interior parts of the action, from the keys to the hammers are unfinished woods. There is no lacquer or finish on the parts. This means the pores of the wood are OPEN and quite willing to accept moisture from the room. The parts swell as the moisture builds, and the piano stops working. Every moving part of the piano is based on a tiny piece of cloth and a pin driven through; these cloth bushings, from the hammers to the whippens, jacks, and even the damper-levers, can swell with humidity and lock-up completely on the pins. It stops working, or works sluggishly in high humidity.

The large panel that is the soundboard is finished, but only with a thin layer. It too will respond fairly quickly to humidity levels in the house. When it swells or expands with moisture it will radically change the sound of the tuning.

None of the tuners on this list can tell you more than; 'Get it dry!' at this time. Suggestions for humidity control systems and the like are meaningless until you get this stabilized in your home. None of us can tell you what it may cost to 'fix'.

If you are lucky, it will be just fine once you get it dry, or at least drier! The Vogel is a nice instrument and deserves a little respect...get it out of there, my friend!

Just a question on this: why is it that piano makers never chose to seal these parts? It seems like it might have been possible to dip many parts in a sealer to reduce the effect of humidity. Maybe you'd have to drill holes after this treatment, but surely having a lot less of the wood exposed to variable conditions would give it more dimensional stability. What do you techs think is the reason for this?

TunerJeff

I have someone coming to deal with the roof on thursday. the piano has gone considerbly out of tune. I am trying to have the local Piano store to come get the Piano tommoroe. Hope no serious damage has been done. Thank-you very much for your knowlegable and kind reply

There is no sealer that will mitigate the effects of humidity on wood. If there was such a discovery it would have been used on sounding boards long ago.

Even sealed wood is subject to the expansion and contraction due to humidity retention or loss.

The material finish would have to be a "vapor barrier" to work. No such material exists; even in construction what is often refered to as a vapour barrier is in fact a vapour diffusion/retarder by strict definition.

The ability of a material to retard the diffusion of water vapor is measured by units known as "perms" or permeability. A perm at 73.4°F (23°C) is a measure of the number of grains of water vapor passing through a square foot of material per hour at a differential vapor pressure equal to one inch of mercury or, 1" W.C. Any material with a perm rating of less than 1.0 is considered a vapor retarder.

Some finishes do come under this amount, but they just slow the process...not eliminate it. They also need to remain thin, and allow the soundboard to freely vibrate. The best vapor diffusers are fairly thick and would deaden the sound.

K-52SM, maybe until you have repaired the roof of your home temporarily set more absorbing materials a piano's place in the room. Such as foam, river sand, wood sawdust etc

Piano manufacturer knowingly fails to do it to possible to reduce the price its products

If it is so bad that there is danger of permanent damage, you should call a damage control specialty company. Your insurance company can recommend one and will probably pay for it.

Thanks Dan and Emmery for your explanation about "sealers". I would assume that if the seal wasn't 100% it would be even worse than no sealer because there would be a significant lag effect. ie moisture trapped within parts would take a long time to be released. I guess that's why carbon fibre actions were developed.

Cheers.

Constant room ventilation is also a way to deal with dampness

"...It has developed a lot of notes that won't play unless repeatedly struck and has gone badly out of tune...."

Ow!

Pianos often go out of tune after they are moved, and sometimes have a sticky key or two (more commonly, new ones). But 90% RH is really bad news, and you should do something, fast. Is it possible to move the piano to a room without a leak, just for now, or to put a dehumidifier in the room to bring it down off the ceiling? Or both.

Try to aim for a steady room humidity of 45-55%, if you can, summer and winter. I grew up in the Deep South (with a piano) and this 100% August humidity is very familiar. Setting aside the dangers of mold and mildew (but of course, we can't), it's the big swings in environmental conditions that are hard on pianos. So try to keep it as steady as you can, and it will do better.

Action parts have typically been left unsealed because areas of contact will wear off the sealer. Being partially sealed in areas and not in others would cause warpage.

I've read somewhere once that the end grain absorbs and releases far more moisture than anywhere else on wood. Perhaps if improvement can be made, it would be in this endgrain area that is contained within the pianos' structure.