5 - Mechanical Engineering

This chapter identifies criteria to program and design heating, ventilating and air conditioning (HVAC) and plumbing systems.

Mechanical systems must be coordinated and integrated with the designs of other involved/impacted building systems and features. As addressed in the Appendix, mechanical systems shall be adapted to support all performance objectives, typically involving sustainability, workplace performance (productivity and efficiency), fire safety, security, historic preservation, and improved operations and maintenance.

Mechanical systems shall be specifically designed to function at full load and part load associated with all projected occupancies and modes of operation. To the maximum extent possible, system solutions shall also accommodate planned future occupancies and modes of operation. (Special emphasis shall be placed on the design considerations for U.S. court facilities to allow for renovation, relocation, and creation of new courtrooms and adjunct facilities or retrofitting courtroom facilities for other agencies’ use. See Chapter 9, “Design Standards for U. S. Court Facilities,” for design criteria. )

The design of the mechanical systems shall generally be more demanding in performance expectations than represented within ASHRAE 90.1 and 10 CFR 434 standards. All mechanical systems shall be designed to automatically respond to the local climatic conditions and heat recovery opportunities to provide cost effective energy conservation measures while assuring set point control. The design of mechanical systems and other building components shall all combine together to produce a building that meets the project’s programmed sustainability rating (LEED rating) and assigned energy target, as referenced in Chapter 1.

Maintainability and reliability are major concerns in the operation of federal buildings. As such, the design and installation of all mechanical equipment and components shall allow for removal and replacement, including major equipment such as boilers, chillers, cooling towers, pumps and air-handling equipment.

Standby capacity shall be designed into mechanical systems, enabling continuous services during repair or replacement of a failed piece of equipment or component. Redundant equipment shall typically not be designed intosystems as “stand-by” units but rather shall be used as part of the operating system with equal time cycling through automatic control sequencing.

Proposed systems and equipment will be evaluated by GSA for their offerings of advanced technology; however, GSA does not allow use of experimental, unproven, or proprietary equipment or systems. Documented proof of historical capability and adaptability of all equipment and systems proposed for a project shall be made available to GSA.

As indicated herein, the description of the mechanical baseline systems establishes the minimum level of quality, function, and performance that may be considered.

Submission requirements are addressed in Appendix A.3.