Is it better to negotiate a faculty offer by email or phone? When negotiating a faculty offer with a search committee chair, is it better to do it via email or phone? Which one is more efficient and can get better results? For example, email have the advantage of written points, while in phone you can sense the other person feedback.
Negotiating the conditions of any future employment is an important conversation.

Most of human communication is non-verbal. We communicate a lot through our voice tone and body language. 

Some people avoid face-to-face, or telephone conversations, as they find the interaction awkward. Ask yourself:- if you were the search committee chair, would you want to employ someone as a lecturer who was uncomfortable in face-to-face communication?

At least offer to have a telephone conversation, or Skype, or video conference with the other party, if a face-to-face meeting is impractical or inappropriate. This shows you are keen to engage in the most efficient means of human-to-human communication. Then follow this up with an email clarifying the main points of your conversation.