There weren't any works going on that I could see, but I didn't walk all the way round the building. The season ends next week so maybe they'll start then?
But on the other hand, Bayreuth's original 1748 opera theatre (The Margravial Opera House) is currently being restored and won't reopen until 2017. It was disappointing not to be able to go on a tour of that the theatre, but apparently a lot of renovation is required. They did at least have a sort of museum upstairs where there was a sort of Ipad which showed the interior of the theatre before the restoration started and we could zoom in and zoom out.
See also http://en.wikipedia.org/wiki/Margravial_Opera_House