Atmosphere

In the past I've ruminated about the importance of atmosphere in the success of educating our students. Such questions inevitably receive answers encouraging us to focus on what we can control--lesson plans, assessment, and classroom management skills.
These responses, while absolutely true in their own right, miss an essential component to influencing individuals. Human nature relies heavily on our emotional responses when confronted with any situation. This truth is evident in our schools across the country. That isn't to say we need to drop millions on remodelling, but we must at least admit that environment is important.
Control what you can control. The reality of public education is that we don't make a profit, and therefore we cannot save up funds to enhance the school atmosphere. However, we can create interactions which severely influence how our students view their time with us.
In the past two weeks, the atmosphere in my building has ranged from controlled chaos to nearly riotous. I get the sense that something has to give.
What does it take to address the toxicity in a school's atmosphere?