Construction in Ile de France

My husband works in construction. He has built all kinds of buildings from pools, to apartments, to town houses to supermarkets to redoing foundations. He has worked all over the Ile-de-France region. Currently he is working about 45 minutes away but he has worked with a commute of 2hours each way and he starts at 7 am.  He works as a mason, he is in charge of the walls. So, when we visit certain Paris monuments, the Patheon, Eiffel Tower, Invalides, etc. he stands there and is like "How did they do this ?" or just random buildings he is like "They messed up that wall etc".

and he does this all year around from extreme heat to cold. Also, it is interesting that most of the workers are Turk, Portuguese and Africans, never the French. But I guess it is like that in the States, there are more Mexican workers than Americans on construction sites.