Project Delivery Method: Design-build (D-B)

Owner Team: Library building manager, facility manager, owner representative (consultant), and physician (consultant)

Project Delivery Team: D-B project manager, coordinator (mechanical-general construction), humidifier consultant, and humidifier service technician

HVAC Project Team: HVAC technician (in-house staff); automatic temperature control (ATC) technician (in-house staff); operation and maintenance technician (in-house staff); third-party commissioning consultant (CxC); third-party testing, adjusting, and balancing (TAB) contractor; and piping foreman

Application 2019 ASHRAE Handbook: Museums, Galleries, Archives, and Libraries, Chapter 24

Systems 2020 ASHRAE Handbook: Steam Systems, Chapter 11

Equipment 2020 ASHRAE Handbook: Jacketed steam humidifiers, Chapter 22, and gas-fired steam generator, Chapter 32

Project Type: Facility audit for IAQ, occupant health, and preservation of the books in the library with a focus on the HVAC infrastructure and capital project master plan following the 2019-2020 pandemic

References: Refer to the codes and standards located at the back of each ASHRAE Handbook for additional reference: 2019 ASHRAE Handbook, HVAC Applications; and 2020 ASHRAE Handbook, HVAC Systems, and Equipment

Other References: ASHRAE Technical Committee TC 5.11, Humidifying and Equipment; and Technical Committee 2.10, Resilience and Security, Construction and Operation of Sustainable Buildings; ASHRAE Humidity Control Design Guide for Commercial and Institutional Buildings; ASHRAE Indoor-Air Quality Guide: Best Practice for Design, Construction, and Commissioning; ASHRAE Standard 55 (Thermal Environmental Conditions for Human Occupancy); and ASHRAE Standard 62.1 (IAQ); and Design-Build Institute of America (DBIA)


  • The HVAC system selection and design intent is based on the process outlined in ASHRAE Handbook 2020, Chapter 1, HVAC System Analysis and Selection, and includes the following:
    • Owner’s building program goals and additional goals
    • System constraints and constructability constraints
    • Finalized system selection based on methods to furnish and install humidification into the library facility
    • Specialized systems shall include a new gas-fired steam generator to produce the steam to new humidifiers in existing central air-handling units and specific areas of the building. Also, a new reverse-osmosis (RO) water system will serve the 100% water makeup to the steam generator.
    • Automatic controls shall include new direct digital steam humidification automation, boiler furnished controls, a BACnet interface, an internet interface, the existing building automation system (BAS) interface, and an interface with the existing computerized maintenance management software (CMMS) system interface
  • Program & Project Goal
    • Functional goals (refer to 2020 ASHRAE Handbook, Chapter 1)
    • Budget goals: first cost and operating cost
    • Timeline goal(s): pre-purchased equipment dates so the humidifiers will be in operation by the upcoming heating season
    • Management goals: A three-year extended warranty service contract for the new steam generator
  • Available utilities: Natural gas and 480/3/60 existing electrical power and BAS system
  • Existing conditions: central air system(s) supply air and/or return air cubic feet per minute (cfm), general and toilet exhaust, heating systems, and air conditioning systems
  • Rebalance and commission the building’s central air systems, new steam generator, humidifier systems, and RO system

    • The HVAC design criteria shall be in sync with the project delivery method and owner’s project requirements
    • The design criteria shall be based on an analytical analysis of the existing facility, occupant, and HVAC conditions; associated operation; and proactive maintenance management
    • The D-B team will refer to the ASHRAE guide for humidity control design and ASHRAE Indoor Air Quality Guide: Best Practice for Design, Construction, and Commissioning
    • The addition of space humidification based on ASHRAE’s Humidity Control Design Guide
    • Owner’s facility environmental audit for space humidification and IAQ, occupant health, and preservation of the books in the library
    • An implementation update of all policy and procedure (P&P) manuals
    • Add humidifiers to recommended existing systems along with the addition of individual space humidifiers as recommended by the D-B humidifier consultant
    • Furnish, install, monitor, measure, and provide monthly reporting (if necessary) of humidity levels, space temperature, and outdoor air temperature
    • Add a new RO water system, serving new building humidifiers furnished and installed per the D-B scope of work
    • The in-house BAS technician will update any existing safeties and alarms associated with the new monitoring and reporting system working with the D-B team, third-party CxC, and third-party TAB technician
    • The facility manager shall have the BAS and operations and maintenance technicians trained to accommodate P&P changes as they affect the building management and HVAC systems
    • The D-B team shall produce complete record documents, warranties, and training
    • The D-B HVAC design engineer shall provide system flow diagrams with these three documents (OPR, DID, and BOD) along with ATC sequences of operation.

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