RFP_Attach_9_Historic_Structure_Report_-_PPR_Appendix_C.pdf

HISTORIC STRUCTURE REPORT

NATIONAL BUREAU OF STANDARDS RADIO BUILDING (BUILDING 1)

U.S. Department of Commerce Boulder Laboratories

Boulder, Colorado June 2018

Prepared by studiotrope Design Collective (sDC)

2942 Welton Street

Denver, Colorado 80205

AECOM

6200 S. Quebec Street

Greenwood Village, Colorado 80111

Prepared for

U.S. Department of Commerce

National Institute of Standards and Technology

Boulder Laboratories

Boulder, Colorado

July 2018

HISTORIC STRUCTURE REPORT

NATIONAL BUREAU OF STANDARDS RADIO BUILDING

(BUILDING 1)

U.S. Department of Commerce Boulder Laboratories

Prepared by studiotrope Design Collective (sDC)

2942 Welton Street

Denver, Colorado 80205 and

AECOM

6200 S. Quebec Street

Greenwood Village, Colorado 80111

Prepared for

U.S. Department of Commerce

National Institute of Standards and Technology

Boulder Laboratories

July 2018

1 Project Data

Project Data

Location

The National Bureau of Standards (NBS) Radio Building (Building 1) is within the U.S. Department of Commerce Boulder Laboratories at 325 Broadway Street in Boulder, Boulder County, Colorado.

Ownership

Building 1 is owned by the U.S. Department of Commerce National Institute of Standards and Technology (NIST).

National Register of Historic Places Status

NIST determined that Building 1 is eligible for listing in the National Register of Historic Places (NRHP) under Criteria A and C. Building 1 is significant under NRHP Criterion A for its associations with the broad patterns of history of the NBS. The building is associated with the growth and expanding research activities of the NBS and the Central Radio Propagation Laboratory in the post-World War II era, when agency activities began to play a key role in Cold War technology and research. When Building 1 was completed, it was considered the flagship building of the Boulder site. With its prominent and visible location along Broadway Street and its cutting edge architecture, Building 1 conveyed the NBS’s image as a progressive and modern agency. The building is significant under NRHP Criterion C as a good example of the International style and of the post-World War II research campus model.

Project Participants

The following personnel assisted with the preparation of and/or contributed to this report:

NIST

Phillip W. Neuberg, FAIA / Architect and Federal Preservation Officer

Wayne Pierce / Architect studiotrope Design Collective (sDC)

Joseph Montalbano / Architecture Principal BS, 1992, Architectural Studies, University of Illinois, Champaign/Urbana MArch, 1994, Arizona State University Licensed Colorado Architect, 1996 Years of Experience: 25

Anne Pharamond / Project Manager and Architect BS, 1994, Marine Science, University of South Carolina MArch, 1998, University of Colorado, Denver Licensed Colorado Architect, 2006 Years of Experience: 22

AECOM

Kirsten Johnson / Lead Historian/Architectural Historian BA, 1996, History, University of Nebraska at Kearney MA, 1999, Public History and U.S. History, Arizona State University Years of Experience: 20

Chris A. (Andy) Paddock / Lead Structural Engineer BS, 1999, Civil Engineering (Structural), Colorado State University Years of Experience: 19

2 Project Data

Ryan E. Meador, PE / Project Manager and Lead Mechanical Engineer BS, 2004, Architectural Engineering, University of Wyoming

Years of Experience: 14

Gordon C. Tucker, Jr. / Cultural Resources Team Lead and Lead Archaeologist MA, 1976, Anthropology, Idaho State University PhD, 1981, Anthropology, University of Colorado at Boulder

Years of Experience: 44

George Verstraete, PE / Lead Electrical Engineer BSc, 1980, Geophysical Engineering

Graduate Studies, Electrical Engineering, University of Colorado and Colorado School of Mines Years of Experience: 24

Alfred Voegels, AIA, PMP, LEED AP / Historic Architect BArch, 1991, Architecture and Urban Design, University of Sao Paulo Years of Experience: 25

Historic Structure Report NIST Boulder Laboratories Building 1 Boulder, Colorado

ES-1 Executive Summary

Executive Summary

ES1. Purpose and Scope

Between 2012 and 2016, the National Institute of Standards and Technology (NIST) completed improvements to Wings 3 and 6 of Building 1, an undertaking under Section 106 of the National Historic Preservation Act (54 US Code 206108). Subsequent to the commencement of those improvements, Building 1 was determined eligible for listing in the National Register of Historic Places (NRHP) in consultation with the Colorado State Historic Preservation Officer (SHPO) for its significance to the history of science and its architectural design. NIST consulted with the SHPO and the City of Boulder pursuant to 36 Code of Federal Regulations (CFR) Part 800, the regulations implementing Section 106, and NIST and SHPO concurred that the undertaking resulted in adverse effects to Building 1. NIST notified the Advisory Council on Historic Preservation (ACHP) of the undertaking in accordance with 36 CFR Part 800.6(a)(1) and ACHP chose to participate in the consultation process pursuant to 36 CFR Part 800.6(a)(1)(iii). In order to mitigate the adverse effect, a memorandum of agreement was subsequently drafted, which stipulated the development of a historic structure report (HSR) with preservation zone plans prior to the implementation of any future phase of improvements to Building 1. This report was completed to fulfill that stipulation.

ES2. Goals of the Historic Structure Report

This HSR was prepared to provide documentary, graphic, and physical information about the history of Building 1 and its existing condition. The goal of this report is to provide NIST with a guide for future improvements to Building 1. This HSR documents the history, construction, and evolution of the building; its historic significance; and its current condition. It also provides historic preservation objectives, selected treatments as defined by the Secretary of the Interior’s Standards for the Treatment of Historic Properties (Standards) (National Park Service [NPS] 2017), and recommendations for work.

ES3. Methodology

The HSR was prepared pursuant to the guidelines set forth in Preservation Brief 43: The Preparation and Use of Historic Structure Reports (Slaton 1995). AECOM’s team included of an architectural historian and a historic architect who meet the Secretary of the Interior’s Professional Qualification Standards for Architectural History and Historic Architecture, respectively, as defined in 36 CFR Part 61. The architectural historian and historic architect were supported by AECOM structural, mechanical, and electrical engineers and studiotrope Design Collective (sDC) architects.

The team conducted an extensive exterior and interior investigation and condition assessment of Building 1. Historical research was conducted using documents obtained from NIST library in Gaithersburg, Maryland; documents, architectural drawings, and historic photos provided by NIST Boulder Laboratories, and archives located at the Carnegie Library for Local History in Boulder.

ES4. Report Findings

ES4.1 Brief Physical Description

Building 1 is located within the NIST Boulder campus at 325 Broadway Street (State Route 93) on the south side of Boulder in Boulder County, Colorado. Access to the campus is by way of a two-lane paved roadway known as Rayleigh Road, which branches off of Broadway Street to the west. Building 1 includes a front portion, known as the “Front of the House”, and three pairs of wings (Wings 1 through 6) radiating outward from a central Spine. Building 1 is on a

ES-2 Executive Summary northeast/southwest axis, with the Front of the House facing northeast and the end of the Spine facing southwest.

Building 1, including the Front of the House, the Spine, and Wings 1 through 4, was completed in 1954, and Wings 5 and 6 were completed in 1962 and 1959, respectively. The building is constructed of cast-in-place, reinforced concrete posts and beams and with a precast concrete tee-joist roof system. The exterior walls are a combination of cast-in-place concrete built using oiled plywood forms and native sandstone. The flat roof is clad with composition roofing in most locations. The Front of the House is on the north end of the Spine and the wings intersect the Spine at equidistant intervals to the south of the Front of the House. The building was constructed on a slight grade and gradually steps up the sloping terrain while the roof of the Spine remains at a constant level.

Building 1 is an example of Modernist architecture with design elements of the International style, which was considered cutting edge in the early 1950s. Those elements include cast-in-place concrete and concrete block construction, a horizontal orientation, a flat roof, horizontal bands of windows, and minimal exterior ornamentation. The building also possesses elements of Functionalism, a variation of the International style based on the theory that building design should emphasize functional efficiency. The building was designed to accommodate the entire laboratory, support, and administrative functions of the Central Radio Propagation Laboratory (CRPL) in one building, with architectural detailing focused on the public and common areas in the Front of the House and more utilitarian design in the Spine and wings to be used as laboratory and office spaces. The building’s architects also appear to have been influenced by Organic Architecture, an American response to European Modernist architecture initiated by Frank Lloyd Wright. This influence is reflected in the architects’ use of the existing terrain in the design of the building, the use of native stone details in the Front of the House, and the low profile of the building designed to preserve views of the Flatirons beyond (City of Phoenix Historic Preservation Office and Ryden Architects 2010).

ES4.2 Condition Assessment

The condition of the building was assessed as good, fair, or poor, with good defined as intact and structurally sound; fair defined as early signs of wear; and poor defined as no longer performing its intended purpose. Building 1 is generally in good condition, including the building envelope, exterior architectural finishes, and weather protection components (joints, windows, and roofing systems), as well as the interior architectural finishes (floors, doors, and ceilings). A few places have been observed to be in fair and poor condition, including portions of the roof, the original windows, exterior doors and hardware, and some concrete finishes. Damages to the concrete include spalling, staining, cracks, and exposed corroding reinforcing bars. Due to the age of the building, numerous mechanical and plumbing features were found to be non-compliant with current codes.

ES4.3 Historic Character-Defining Features

All extant original exterior elements of Building 1 contribute to its character and its eligibility for listing in the NRHP. On the interior, character-defining features are concentrated in the Front of the House, which, as the original public entrance to the campus and the location of the building’s common areas, possesses all the building’s architectural ornamentation while the rest of the building is more utilitarian in design. To support the scientific mission of the NBS and the CRPL, alterations to the interior of Building 1 began soon after the building was constructed and have continued throughout the building’s history. The historic integrity of the laboratory and office spaces in the Spine and wings has been compromised by these alterations, and the only character-defining features that remain intact in the interior of the Spine and wings are the configuration of the double-loaded corridors. Major character-defining features are described in detail in the following sections.

ES-3 Executive Summary

Site

The spatial relationship of the Building 1 footprint, the lawns and landscaped exterior courtyard at the Front of the House, and the outdoor spaces between the wings.

The setting of the building within the topography of the site, including the Spine’s position within the existing slope and the ascending intersections of the wings.

The axial siting of the building toward Broadway Street.

Exterior

Modernist architecture with design elements of the International Style, Organic architecture, and Functionalism.

Overall configuration, massing, and scale as a singular large resource with common areas with expansive office and laboratory wings.

Exterior wall finishes, including native sandstone and cast-in-place concrete.

Low, horizontal orientation emphasized by flat roofs, horizontal bands of windows, bays formed by exposed concrete structural post and beam, rooftop monitor clerestories in the wings, and contrasting vertical divisions in the Front of the House.

Extant concrete sunshades above the windows on the Spine and Wings 1, 2, and 4.

Interior

The north, south, and central division floor plan in the Front of the House and the north end of the Spine including the auditorium, library, and lobby/entrance space.

Extant original Interior finishes in the Front of the House including:

o terrazzo flooring and baseboards;

o travertine wall panels;

o original single- and double-leaf wood doors;

o exposed native sandstone walls;

o birch and walnut plywood paneling;

o built-in display cases in the foyer;

o jagged/sloping pattern of east and west auditorium walls

Configuration of the double-loaded corridors (central corridors with offices and laboratory spaces on either side) in the Spine and the wings.

ES4.4 Historic Preservation Objectives and Work Recommendations

The Standards identify four treatment approaches for historically significant resources such as Building 1 – Preservation, Rehabilitation, Restoration, and Reconstruction. Given the goals of NIST, the most appropriate treatment approach for Building 1 is Rehabilitation, which would preserve materials and features that convey the building’s historical and architectural values, while allowing for the necessary repairs and upgrades.

As part of its 2017 Master Plan (Metropolitan Architects and Planners 2017a), NIST initiated a phased renovation and upgrade program for Building 1 to replace outdated systems and meet the performance level required for NIST’s research. The renovations of Wings 3 and 6 were previously completed. Future projects to renovate the remaining sections of the building, including the Front of the House, the Spine, and Wings 1, 2, 4, and 5, should be designed and executed in accordance with the appropriate recommended NPS standards and guidelines for rehabilitation (NPS 2017). Future designs should be analyzed on a case-by-case basis by professionals meeting the Secretary of the Interior’s Professional Qualification Standards for History and Architectural History, as well as Historic Architecture, if warranted, to determine if those projects meet the appropriate recommended Standards.

ES-4 Executive Summary

Specific work recommendations were made for the structural, mechanical and plumbing, and electrical aspects of Building 1, including repairs to the structural concrete; recommendations for seismic retrofit and occupancy and uses; replacement of original windows and doors with in-kind or compatible types; and other recommendations regarding insulation, roof assemblies;

heating, ventilation, and air conditioning (HVAC); plumbing, and electrical systems.

ES5. Organization of the Report

The HSR is organized into three parts as follows:

Part 1 – Developmental History

Chapter 1 provides the historical background and context of Building 1, including a brief history of the property, its context, and its designers and builders.

Chapter 2 provides a chronology of development and use, including a description of original construction, modifications, and uses, based on historical documentation and physical evidence.

Chapter 3 provides a physical description and condition assessment.

Chapter 4 includes a statement of significance, identifies character-defining features, and provides an assessment of historic integrity.

Part 2 – Treatment and Work Recommendations

Chapter 5 provides a description and rationale for the recommended treatment approach, and how it meets the project goals for Building 1. It also includes an explanation of the historic preservation treatment zones and the areas of the building assigned to each zone.

Chapter 6 provides a description of the requirements for work, and presents tasks recommended to realize the proposed treatment approach.

Part 3 – Bibliography and Appendices

Chapter 7 provides information about the sources used in preparing the report.

Five appendices are included in this report as follows:

Appendix A – NIST Historic Assessment Report

Appendix B – Architectural Drawings

Appendix C – Photographs

Appendix D – Preservation Zoning Plans

Appendix E – Preservation Briefs i Table of Contents

TABLE OF CONTENTS

1. Historical Background and Context .................................................................................. 1-1

1.1 National Bureau of Standards – 1901 to World War II ............................................... 1-1

1.2 Central Radio Propagation Laboratory – 1946 to 1954 ............................................. 1-3

1.3 NBS Boulder Laboratories – 1954 to 1965 ................................................................ 1-6

1.4 U.S. Department of Commerce Boulder Laboratories – 1965 to the Present............. 1-6

2. Chronology of Development and Use ............................................................................... 2-1

2.1 Planning .................................................................................................................... 2-1

2.2 Construction.............................................................................................................. 2-4

2.3 Original Appearance ................................................................................................. 2-7

2.3.1 Exterior Description............................................................................................ 2-8

2.3.1.1 Spine .............................................................................................................. 2-8

2.3.1.2 Front of the House ........................................................................................ 2-14

2.3.1.3 Wings 1 through 4 ........................................................................................ 2-19

2.3.1.4 Wing 6 .......................................................................................................... 2-26

2.3.1.5 Wing 5 .......................................................................................................... 2-28

2.3.2 Interior Description ........................................................................................... 2-29

2.3.2.1 Front of the House ........................................................................................ 2-29

2.3.2.2 Spine ............................................................................................................ 2-37

2.3.2.3 Wings 1, 2, 3, 4, and 6 ................................................................................. 2-46

2.3.2.4 Wing 5 .......................................................................................................... 2-47

2.4 Alterations ............................................................................................................... 2-55

3. Physical Description and Condition Assessment .............................................................. 3-1

3.1 Architecture............................................................................................................... 3-1

3.1 General Architectural Conditions Assessment Overview ....................................... 3-1

3.1.2 Exterior and Building Envelope Observations .................................................... 3-3

3.1.2.1 Front of the House .......................................................................................... 3-3

3.1.2.2 Spine .............................................................................................................. 3-4

3.1.2.3 Wing 1 ............................................................................................................ 3-5

3.1.2.4 Wing 2 ............................................................................................................ 3-6

3.1.2.5 Wing 3 ............................................................................................................ 3-6

3.1.2.6 Wing 4 ............................................................................................................ 3-7

3.1.2.7 Wing 5 ............................................................................................................ 3-7

3.1.2.8 Wing 6 ............................................................................................................ 3-8

3.1.3 Interior Observations .......................................................................................... 3-8

3.1.3.1 Front of the House .......................................................................................... 3-8

3.1.3.2 Spine ............................................................................................................ 3-11

3.1.3.3 Wings 1, 2, 4, and 5 ..................................................................................... 3-13

3.1.3.4 Wings 3 and 6 .............................................................................................. 3-13

3.2 Engineering............................................................................................................. 3-13 ii Table of Contents

3.2.1 Structural ......................................................................................................... 3-14

3.2.1.1 Original Structural Systems .......................................................................... 3-14

3.2.2 Mechanical / HVAC and Plumbing ................................................................... 3-16

3.2.2.1 Original Mechanical Systems ....................................................................... 3-16

3.2.2.2 Current Mechanical Systems ........................................................................ 3-18

3.2.2.3 Plumbing ...................................................................................................... 3-20

3.2.3 Electrical .......................................................................................................... 3-22

3.2.3.1 Original and Current Electrical Systems ....................................................... 3-22

4. Evaluation of Significance ................................................................................................ 4-1

4.1 Statement of Significance ......................................................................................... 4-1

4.2 Historic Character-Defining Features ........................................................................ 4-2

4.2.1 Site .................................................................................................................... 4-2

4.2.2 Exterior .............................................................................................................. 4-2

4.2.3 Interior ............................................................................................................... 4-2

4.3 Assessment of Integrity ............................................................................................. 4-3

5. Historic Preservation Objectives ...................................................................................... 5-1

5.1 Introduction ............................................................................................................... 5-1

5.2 Secretary of the Interior’s Standards ......................................................................... 5-1

5.2.1 Preservation ...................................................................................................... 5-1

5.2.2 Rehabilitation ..................................................................................................... 5-2

5.2.3 Restoration ........................................................................................................ 5-2

5.2.4 Reconstruction ................................................................................................... 5-2

5.3 Application of Standards and Treatment to Building 1 ............................................... 5-2

5.3.1 Zone 1 – Preservation Treatment Zone.............................................................. 5-3

5.3.2 Zone 2 – Rehabilitation Treatment Zone ............................................................ 5-4

5.3.3 Zone 3 – Renovation Zone................................................................................. 5-5

6. Requirements for Work and Work Recommendations ...................................................... 6-1

6.1 Requirements for Work ............................................................................................. 6-1

6.2 Work Recommendations ........................................................................................... 6-1

6.2.1 Structural ........................................................................................................... 6-2

6.2.2 Mechanical and Plumbing .................................................................................. 6-3

6.2.3 Electrical ............................................................................................................ 6-4

7. References ...................................................................................................................... 7-1

Appendices

Appendix A – NIST Historic Assessment Report

Appendix B – Architectural Drawings

Appendix C – Photographs

Appendix D – Preservation Zoning Plans

Appendix E – Preservation Briefs iii Table of Contents

LIST OF FIGURES

FIGURE PAGE

1-1 General Project Location....................................................................................................... 1-2

1-2 Boulder Site Prior to the Construction of NBS Facilities ....................................................... 1-4

1-3 President Dwight Eisenhower at the Dedication of Building 1 .............................................. 1-5

1-4 Atomic Clock NBS-1 .............................................................................................................. 1-7

1-5 Atomic Clock NBS-2 .............................................................................................................. 1-7

1-6 Atomic Clock NBS-6 .............................................................................................................. 1-8

2-1 Building 1 Site Plan, Drawing A-2-1 ...................................................................................... 2-2

2-2 Concrete Sunshades on the Spine ....................................................................................... 2-3

2-3 Drawing of Concrete Sunshades .......................................................................................... 2-3

2-4 Building 1 under Construction ............................................................................................... 2-4

2-5 Wing 3 and Spine under Construction .................................................................................. 2-4

2-6 Building 1 in the Mid-1950s ................................................................................................... 2-5

2-7 Building 1 Circa 1960 ............................................................................................................ 2-6

2-8 Wing 6 under Contruction ..................................................................................................... 2-6

2-9 Building 1 after the Construction of Wing 5........................................................................... 2-7

2-10 Aerial Photograph of Building 1 ............................................................................................ 2-9

2-11 Building 1 in the Mid-1950s ................................................................................................... 2-10

2-12 East Side of the Spine South of Wing 4 ................................................................................ 2-10

2-13 East Elevation of Spine, Drawing A-4-5 ................................................................................ 2-11

2-14 Spine Elevations, Drawing A-4-1, Ext.1 ................................................................................ 2-12

2-15 Rooftop Penthouse and Boiler Stack .................................................................................... 2-13

2-16 South End of the Spine under Construction.......................................................................... 2-14

2-17 Front of the House Elevations and Sections, Drawing A-4-1................................................ 2-15

2-18 Building 1 in the Mid-1950s ................................................................................................... 2-16

2-19 North End of the Spine at the Front of the House ................................................................. 2-16

2-20 North Elevation of the Library at the Front of the House ...................................................... 2-17

2-21 East Elevation of the Library at the Front of the House ........................................................ 2-17

2-22 Open Patio and Main Entrance Vestibule ............................................................................. 2-18

2-23 Auditorium Section of the Front of the House ....................................................................... 2-19

2-24 North Elevations Wings 1 and 2, Drawing A-4-7 .................................................................. 2-20

2-25 South Elevations Wings 1 and 2, Drawing A-4-8 .................................................................. 2-21

2-26 North Elevations Wings 3 and 4, Drawing A-4-9 .................................................................. 2-22

2-27 South Elevations Wings 3 and 4, Drawing A-4-10 ................................................................ 2-23

2-28 East and North Elevations of Wing 2 under Construction.................................................... 2-24

2-29 South Elevation of Wing 1 under Construction ..................................................................... 2-25

2-30 North Elevation of Wing 4, East Elevation of Spine, and South Elevation of Wing 2 ........... 2-25

2-31 South and East Elevations of Wings 4 and 2 ........................................................................ 2-26

2-32 West and East Elevations of Wings 1 through 4, Drawing A-4-11 ....................................... 2-27

2-33 East and North Elevations of Wing 6 .................................................................................... 2-28

2-34 North Elevation of Wing 5 ..................................................................................................... 2-29

2-35 Front of the House Floor Plan, Drawing A-3-1 ...................................................................... 2-31

2-36 South Wall of the Lobby ........................................................................................................ 2-32

2-37 Lobby looking east toward the library ................................................................................... 2-32

2-38 Staircases to Levels 1 and 2 of the Spine............................................................................. 2-33

2-39 North Wall of Library ............................................................................................................. 2-33 iv Table of Contents

2-40 West and North Wall of Library ............................................................................................. 2-34

2-41 Lobby and Foyer looking north toward the Auditorium ......................................................... 2-35

2-42 North Wall of Foyer, from Drawing A-5-27 ............................................................................ 2-36

2-43 Auditorium Projection Room Floor Plan, from Drawing A-3-9 .............................................. 2-37

2-44 Auditorium Interior Elevations, Drawing A-5-29 .................................................................... 2-38

2-45 Auditorium Floor Plan, Drawing A-3-1 .................................................................................. 2-39

2-46 South and West Walls of Auditorium under Construction ................................................................. 2-40

2-47 South and West Walls of the Auditorium and Auditoriam Seats ........................................... 2-40

2-48 Stage and West Stage Door under Construction .................................................................. 2-41

2-49 Spine Level 1 Floor Plan, from Drawing A-3-2 ..................................................................... 2-42

2-50 Spine Level 2 Floor Plan, from Drawing A-3-3 ..................................................................... 2-44

2-51 Office Room in the Spine under Construction ...................................................................... 2-45

2-52 Office/Laboratory Room in Building 1 ................................................................................... 2-45

2-53 Office/Laboratory Room in Building 1 ................................................................................... 2-46

2-54 Wings 1 and 2 Floor Plans, Drawing A-3-4 ........................................................................... 2-48

2-55 Interior CMU Walls, Room 358, Wing 3, under Construction ............................................... 2-49

2-56 Interior of Room 358, Wing 3, under Construction ............................................................... 2-49

2-57 Shop Area in Wing 3 ............................................................................................................. 2-50

2-58 Wing 3 Floor Plan, Drawing A-3-6 ........................................................................................ 2-51

2-59 Wing 4 Floor Plan, Drawing A-3-7 ........................................................................................ 2-52

2-60 Wing 5 Third Floor Plan, Drawing A-3-2 ............................................................................... 2-53

2-61 Wing 5 Fourth Floor Plan, Drawing A-3-3 ............................................................................. 2-54

3-1 Building 1 Steam Plant Design ............................................................................................. 3-17

3-2 Building 1 Perimeter Heating Design .................................................................................... 3-17

3-3 Wing 5 ................................................................................................................................... 3-19

3-4 Wing 1 ................................................................................................................................... 3-19

3-5 Wing 5 ................................................................................................................................... 3-22

LIST OF TABLES

TABLE PAGE

2-1 Major Exterior Alterations and Selected Interior Modifications ............................................. 2-55

3-1 Condition Definitions .................................................................................................................... 3-1

3-2 Architectural Condition Assessment Summary – Exterior .................................................... 3-2

3-3 IECC 2015 Building Envelope Requirements for Climate Zone 5 ........................................ 3-21

5-1 Secretary of the Interior’s Standards for Rehabilitation ........................................................ 5-3 v Table of Contents

ACRONYMS AND ABBREVIATIONS

ACHP Advisory Council on Historic Preservation

ADA Americans with Disabilities Act

AEC Atomic Energy Commission

AIA American Institute of Architects

ASHRAE American Society of Heating, Refrigeration and Air-Conditioning Engineers

ASTM American Society for Testing and Materials

CFR Code of Federal Regulations

CMU concrete masonry units

CRPL Central Radio Propagation Laboratory

CUP Central Utility Plant

DOAS dedicated outdoor air system

FM frequency modulation

ESSA Environmental Science Service Administration

GSA U.S. General Services Administration

HSR Historic Structure Report

HVAC Heating, Ventilation, and Air Conditioning

IBC International Building Code

IECC International Energy Conservation Code

IRPL Interservice Radio Propagation Laboratory

LEED Leadership in Energy and Environmental Design

Low-E low emissivity

LPD lighting power densities

MEMS Micro-Electromechanical Systems

NBS National Bureau of Standards

NFPA National Fire Protection Association

NIST National Institute of Standards and Technology

NOAA National Oceanic and Atmospheric Administration

NPS National Park Service

NRHP National Register of Historic Places

NTIA National Telecommunications and Information Administration

OSHA Occupational Safety and Health Administration

PBS Public Buildings Service psf pounds per square foot psi pounds per square inch sDC studiotrope Design Collective

SHPO State Historic Preservation Officer

Standards Secretary of the Interior’s Standards

TPO thermoplastic polyolefin

UHF ultra-high frequency

VCT vinyl composition tile

VHF very high frequency

PART 1: DEVELOPMENTAL HISTORY

1-1 Historical Background and Context

1. Historical Background and Context

The National Bureau of Standards (NBS) Radio Building (Building 1) is located at 325 Broadway Street (State Route 93) on the south side of Boulder in Boulder County, Colorado (Figure 1-1).

The NBS constructed Building 1 to serve as the headquarters of its Central Radio Propagation Laboratory (CRPL) division in 1954. Building 1 is significant for its associations with the growth and expanding research activities of the NBS and the CRPL in the post-World War II era, when agency activities began to play a key role in Cold War technology and research. At the time of its construction, the Modernistic architecture of Building 1 was cutting edge, and with its prominent and visible location along a major thoroughfare (State Route 93/Broadway Street) in Boulder, the building conveyed the NBS’s image as a progressive and modern agency. The building also is significant as a good example of Modernist architecture and the post-World War II research campus model.

A detailed historical background and context of the NBS, the U.S. Department of Commerce National Institute of Standards and Technology (NIST), the Boulder Campus, and Building 1 is included in the report titled Historic Assessment Department of Commerce Boulder Laboratories for National Institute of Standards and Technology, Boulder, Colorado prepared for NIST in April 2016 by R. Christopher Goodwin & Associates of Frederick, Maryland (Gatewood and others 2016; Appendix A). A concise summary of the historical background and context of Building 1 was developed using information obtained from that report and other primary and secondary sources and is provided below.

1.1 National Bureau of Standards – 1901 to World War II

Congress established the NBS in 1901 to serve as the national standards laboratory for the United States. The new agency assumed the duties of the Office of Standard Weights and Measures, which was founded in 1836 as part of the Coast and Geodetic Survey to develop standardized measurements for the assessment of goods shipped both across state lines and internationally. The NBS was initially part of the Department of the Treasury, but two years later was transferred to the Department of Commerce and Labor. In 1913, the Department of Commerce and Labor was divided into separate agencies, and NBS was placed within the Department of Commerce. The NBS headquarters was located in Washington, D.C., and the agency was initially divided into three research divisions – Division 1, which included weights and measures, heat and thermometry, lights and optical instruments, engineering instruments, instrument shop, and administration; Division 2 for electricity; and Division 3 for chemistry (Gatewood and others 2016).

Radio research began at the NBS in the early twentieth century with research into the practical applications of radiotelegraphy. During World War I, NBS radio research contributed to the war effort, including the development of an improved radio direct finder used to locate enemy positions. In 1913, the Radio Laboratory Section of the NBS was established and designated as Section 6 of the Electricity Division (DeWeese and others 2004; Gatewood and others 2016).

After the war, Secretary of Commerce Herbert Hoover redefined the NBS mission to support domestic economic recovery through the establishment of standards of quality, simplification of articles of commerce, reduction of unnecessary varieties, and development of uniform business documents. Standards were developed for building construction materials and codes, fuel economy, and auto safety. The agency also created methods to test fire endurance of buildings and improved dental materials. Radio research in the post-World War I era included investigations into standardized radio frequencies for the advancement of the home radio and the development of a radio guiding system for aircraft (Gatewood and others 2016).

1-2 Historical Background and Context

Figure 1-1. General Project Location

1-3 Historical Background and Context

Research during the Depression era was generally redirected to standards and improved methods of measurement, but research of radio transmission and receiving continued. In 1923, the NBS constructed a radio station, with the call sign WWV, in Beltsville, Maryland, to continuously transmit official United States government frequency and time signals. The station is still in use and currently the oldest continuously operating radio station in the country. Other radio research efforts focused on the study of radio interference in the layers of the upper atmosphere and the linkage between long-distance radio interruptions and sun eruptions. Other research involved studies on X-rays, radium, and atomic studies, including early development efforts of the atomic bomb (Gatewood and others 2016).

During World War II, research conducted by NBS scientists and engineers supported the war effort and military objectives. This classified research resulted in a dramatic increase in the numbers of NBS staff and in the agency’s budget. Many wartime projects focused on radio research, including the improvement of radio direction finders and the study of radio propagation, aerial navigation, radio-telegraphy, and radar. Utilizing funding it received from the military, the NBS established a new division of the agency known as the Interservice Radio Propagation Laboratory (IRPL) in 1942. The mission of the IRPL was to predict the behavior of transmitted radio waves to facilitate the selection of radio frequencies and military communications planning (Gatewood and others 2016; Passaglia 1999).

1.2 Central Radio Propagation Laboratory – 1946 to 1954

Technological advancements made during World War II transformed the fields of science and technology. After the war, the NBS served as the federal government’s principal agency for research in physics, mathematics, chemistry, and engineering. By 1950, the NBS had 3,100 personnel staffing 15 research divisions containing 107 sections, and a budget of $20 million (Gatewood and others 2016).

After World War II, the military and government agencies requested that the work of the IRPL expand to focus primarily on radio research for civilian use. In 1946, the CRPL was created and consumed the former IRPL. The new division was administered by the NBS and directed by an executive council, including members from the military and government agencies (Army, Army Air Forces, Navy, Federal Communications Commission, Civil Aeronautics Administration, Coast Guard, and NBS) and the private radio industry (Radio Technical Planning Board). With the establishment of the CRPL, the NBS combined its research on radio propagation and radio standards and forecasting into one division. During World War II, microwave radio was recognized for its contributions to the military, and during the subsequent Cold War, scientific research refined microwave radio for use in surveillance, navigation, and communication. Post-war activities of the CRPL included research on line-of-sight microwave propagation, new ranges of radio frequencies, and the troposphere and ionosphere as media for the propagation of radio waves, as well as the development and maintenance of the national primary standards for radio frequency measurements (Gatewood and others 2016; Kamper 1992; Passaglia 1999).

Just one year after its establishment, the CRPL had become the largest division in the NBS with a staff of 414 and received 30 percent of the agency’s Congressional funding (Schooley 2006).

As the staff of the CRPL and other NBS divisions grew, the agency realized that its Washington, D.C. campus was no longer adequate to house the CRPL. No building on the campus was large enough to house the entire CRPL, and necessary upgrades to bring existing buildings up to current research standards would have been costly. Radio studies in Washington, D.C. also were impaired by interference from large amounts of radio traffic in the surrounding city and the lack of an unobstructed horizon to study line-of-sight radio propagation (Kamper 1992). In October 1949, Congress authorized the expenditure of $4.4 million for the construction of a new radio building. The Secretary of Commerce and the NBS director were placed in charge of selecting the building site (Snyder and Bragaw 1986). In addition to radio quiet and

1-4 Historical Background and Context unobstructed horizons, the selected site also needed to be near a university with a strong electrical engineering program and have room for expansion. Congress also stipulated that the building location be outside of Washington, D.C. as a precaution against nuclear attack.

Boulder, Colorado was selected as a finalist due to its compatible environment for CRPL programs and its proximity to the University of Colorado at Boulder. In February 1950, the Boulder Chamber of Commerce formed the Bureau of Standards Committee, which initiated a campaign to raise $70,000 to purchase 217 acres south of Boulder for the construction of the NBS facility (Figure 1-2). By the end of April, the committee had raised more than $90,000 from local citizens and purchased the property. NBS subsequently selected the Boulder site and on June 14, 1950, the Chamber of Commerce transferred the deed to the land to the United States government (Gatewood and others 2016; Kamper 1992).

Figure 1-2. Boulder Site Prior to the Construction of NBS Facilities; Published in the Boulder Daily Camera on December 15, 1949 (Snyder and Bragaw 1986)

Preliminary design of Building 1 began almost immediately after Congress authorized the expenditure. The new building would accommodate the entire laboratory, support, and administrative functions of the CRPL in one structure and was initially planned to be the only building on the Boulder campus. However, following the acquisition of the Boulder property, President Truman announced the intent of the United States to build a “super” bomb and the continuation of the development of atomic weapons for national security. Because the Boulder campus was close to the Atomic Energy Commission’s (AEC) new Rocky Flats Plant, the AEC asked Congress to authorize the construction of cryogenic and liquid hydrogen plants on the Boulder campus. These plants, which became Buildings 2 and 3, respectively, were constructed in 1951 as the NBS Cryogenic Engineering Laboratory/Division at Boulder prior to construction of Building 1. Building 4, or the Camco Building also was constructed at this time (Gatewood and others 2016; Schooley 2006; Snyder and Bragaw 1986).

Some NBS staff had arrived in Colorado as early as 1950, when the CRPL initiated the Cheyenne Mountains projects to study tropospheric propagation in the Colorado Springs area.

Other staff arrived in Boulder in the spring of 1951 and temporarily occupied the Colorado National Guard Radar Armory and warehouse on the north side of Boulder until Building 1 was

1-5 Historical Background and Context complete. Construction of Building 1 began in the late spring of 1952 and was complete by the fall of 1954. NBS staff began to move into Building 1 in late April 1954. In early May and throughout the summer, staff of the CRPL and other NBS divisions arrived in Boulder from Washington, D.C. Because the CRPL Radio Standards Division was the keeper of the National Standard of Frequency and Time Interval, the national standard also had to be moved from Washington, D.C. to Building 1. At that time, the national frequency standards were a set of quartz crystal oscillators that had to be kept at a consistent temperature. Radio frequencies were determined by the rate at which a charge of electricity made thin slices of the quartz vibrate and were used to calibrate frequency measuring instruments and control the frequencies broadcast by NBS radio stations in Maryland and Hawaii. The standards were hand carried by CRPL staff to the Washington, D.C. airport, transported by air to Denver, where they were met by Colorado CRPL staff (Gatewood and others 2016; Passaglia 1999; Perkin 1954; Snyder and Bragaw 1986).

In a ceremony held on September 14, 1954, President Dwight D. Eisenhower formally dedicated Building 1 at the NBS Boulder campus (Figure 1-3). Prior to the dedication, NBS held week-long scientific conferences. At the time of the building’s completion, it was the nation’s largest and most modern radio propagation laboratory (The Boulder Daily Camera 1954a).

Figure 1-3. President Dwight Eisenhower at the dedication of Building 1 on September 14, 1954 (photograph courtesy of Carnegie Library for Local History, Boulder, Colorado, Chamber of Commerce Collection)

1-6 Historical Background and Context

1.3 NBS Boulder Laboratories – 1954 to 1965

After the CRPL…