When Barton Associates was tasked with designing the domestic water system for the Nemours Children’s Health Specialty Care & Ambulatory Center located in Malvern, PA, cost savings for the owner and simplifying construction for the contractor were on our minds. Typical domestic water systems plumb cold water and 110°F hot water to most fixtures; however, Barton Associates designed a system utilizing tempered water in lieu of hot water.
Section 607 of the 2018 International Plumbing Code allows tempered water to be supplied for bathing and washing purposes in nonresidential occupancies. Tempered water is defined in chapter 2 of that code as water having a temperature range between 85°F (29°C) and 110°F (43°C).
By utilizing a tempered water system for bathing and washing purposes, Barton was able to design and specify a domestic water system that reduced the required piping to the sinks and lavatories by half as well as negating the need for point-of-use tempering valves at those fixtures. Additionally, since Pennsylvania’s commercial energy code only requires pipe insulation on water piping where water is greater than 105°F according to section C404.4, Insulation of Piping and table C403.11.3 Minimum Pipe Insulation Thicknesses, pipe insulation can also be omitted on tempered water piping so long as the tempered water is below 105°F, saving even more costs for the owner. Since the tempered water is maintained above the space dewpoint temperature, there’s never an opportunity for that piping to sweat and cause damage to ceilings and other parts of the building.
If your project allows the inclusion of a tempered water system instead of a hot and cold water system, there’s significant time, cost, and effort that can be saved by implementing a tempered water system.
Barton Associates has over five decades of experience designing and specifying domestic water systems. If you have specific questions regarding the appropriate use and implementation of a tempered water system in your facility, please contact David A. Taylor, PE, ASSE 6060, at dat@ba-inc.com.