Sefer Chofetz Chaim Chapter 3, halacha 5, note 5, with the footnote

Today we discussed that even in a casual manner if you say something which at first glance might not seem negative but your in trickery intent is to throw in a negative fact bout someone, even if hinted to and said straight out, it is still forbidden. 

I gave an example of two neighbors schmoozing about a new family that moved into town and they were discussing how it is a big family with 7 children and they seem to be a very nice and polite family, simple, moving into a 3 bedroom house. One neighbor just wonders how they can fit any guests but then  says he is excited to meet them and get to know them!  

That line thrown in about guests was a casual remark not meaning to be out right malicious but it might imply that this family is not as hospitable then they outwardly seem. That is lashon hara.

Even to possibly just say they are a simple family of 9 living in a 3 bedroom house would be at least avak lashon hara (rabbinic, dust of lashon hara) because that will imply they aren’t hospitable. Of course as we learned before the permissibility or forbiddance of avak lashon hara depends on one’s tone and intent was it meant to be positive or negative, and how did it come out.