Consulting engineers are often unsure about how prescriptive vs. how performance-based their specifications should be. This presentation describes how one firm approaches this, mainly from a prescriptive standpoint, and what they specify. It covers water analysis and how it relates to both domestic and hydronic systems. Other topics covered are cleaning of piping systems, water treatment for corrosion reduction in hydronic systems, best practices for glycol systems, and a brief synopsis of Legionella suggestions based on ASHRAE Standard 188.