This is just a question that has been plaguing my mind for a while. How long does a commonly used Muppet last before they are worn out? How about Muppets that aren't used anymore? I know that sometimes there are Muppets on display in museums that need to be kept in a climate controlled environment. Are they that fragile? Are some more fragile than others?
Where these questions are coming from, I don't know. I was just curious.
Commonly puppets are built to last for a good 3-5 years... there is the common wear and tear with seams and so forth but usually they'll be built to last. Some puppets are built just to mess up! Or for example: Miss Piggy in "Muppets Take Manhattan" when she puts on all that makeup..
They're ruining the puppet... But it's either been a "stunt piggy" or what have you that's been refurbished to be used for such a scene. Just like the scene with Miss Piggy in "Muppet Family Christmas" with the mud slinging from the taxi.
Big Bird gets refeathered every 4-5 years on account his feathers turn green under the studio lights after a while.
A lot of times you can notice how his feathers are replaced or put on differently from the last couple of seasons. You can also tell which puppet is which.
For instance, Bear in the Big Blue House... Around the end of the series, Bear had better eye blinks as well as seemed a bit bulkier. He was refurbished due to wear and tear and or rebuilt. Again, this is usually just something that has to be done or another reasoning is that there could be an added feature to the puppet. For instance, Treelo around the end of the series had eye-blinks! It gave him more expression..