the pronounciation of "buildings"
In American English, if a word ends in voiced consonants, then when you add an S, continue the vocing throughout the entire word,and it should become a voiced zzzz.
So, "things" pronounce "[θɪŋz]", "songs" pronounce "[sɔ:ŋz] ", "buildings" pronounce "[ˈbɪldɪŋz] ", is that right?

Question

the pronounciation of "buildings"
In American English, if a word ends in voiced consonants, then when you add an S, continue the vocing throughout  the entire word,and it should become a voiced zzzz.
So, "things" pronounce "[θɪŋz]",  "songs" pronounce "[sɔ:ŋz] ", "buildings" pronounce "[ˈbɪldɪŋz] ",  is that right?

Answer

The rule is the same in any English. It's not only an American thing.

It's simply easier to say that way!