Decay of concrete on Bauhaus buildings...

One of the first Bauhaus buildings (there are 4.000 of them in the inner-city of Tel Aviv!) that was restored (in 1994), is the beautiful building in Bialik Street no. 18 (architect: Friedman Bros, 1935). A few days ago, I did a Bauhaus tour with a Dutch reporter and saw the building again, after quite a long time.
I was quite shocked: the building has signs of decay of concrete again!!
Please, Tel Aviv, once you restore a building, don’t wait another 50 years again, but keep an eye on your (beautiful) restored buildings!!! Please?!