Sean P. Mulligan headshot
Sean Mulligan – Mission Critical



20+ years of progressive leadership experience completing complicated builds of data centers, trading floors, financial centers, corporate headquarters, and laboratories across the continental U.S. Client-Focused Leader who orchestrates all project phases of challenging and multiphase builds while simultaneously driving efforts to optimize efficiency and quality, reduce project costs and waste, and increase staff utilization and bottom-line revenue. Fluent in VDC, BIM, project management, and scheduling software. Recently led launch of Walbridge’s Mission-Critical division, took ownership of the first-ever project, and landed $300M contract for a hyperscale data center in Virginia.

Data Center Projects

Amazon Data Centers, Columbus, OH – Fit-out and commissioning of AWS data center “pods” with electrical, mechanical, and controls support spaces. Fast-track build in a phased approach using proprietary methods and OFCI items: generators, switchgear, UPSs, ATSs, AHUs, HAC, busway. Positioned company to win larger contracts or entire buildings.

 Microsoft Data Centers, Boydton, VA – Fit-out and commissioning of BN9-13 (approx. 75 mW in 454,000-sq.-ft buildings). Build began with demo, then a ground-up build incorporating 43 generators, 160 external AHUs, and 25,000+ pieces of equipment to take through five levels of commissioning. LEED Gold project on very tight schedule and constrained site.

SoCal Edison Data Center, Irvine, CA – Led a live-environment build of a fully commissioned, NERC-standard, highly secured 132rack data center within existing SCE property. Added 1.5-mW generator; upgraded three existing generators to digital; extended and upgraded paralleling switchgear; MEPS and life safety; integration via MOPs to every bit of live infrastructure.

Microsoft Data Center, Boydton, VA, $350M Budget – With general contractor (GC) oversaw out-of-the-ground construction of new 32-mW data-center buildings and civil infrastructure. As owner’s rep. (Linesight), managed multiple projects in five production data centers (over 100 mW). Coordinated multiple teams to define project scope, bid to street, analyze/level bids, award work, and manage to close-out. Spearheaded teams to pinpoint and replace failing equipment. Drove thought process while minimizing risk.

 Knight Equity Markets, Purchase, NY – Managed white-space expansion of a 19,000-sq.-ft. N+1 live trading floor data center, including build-out of electrical infrastructure rooms, a disaster recovery area (60+ desks), exterior equipment yard, and site hardening. Oversaw installation of 2,000-amp electrical services, a 1.5-mW generator, 130-ton chillers, and all equipment.

 Thomas Reuters, Valhalla, NY – Supervised expansion of 8,000-sq.-ft. production data center, including installation of a new power riser, UPS on new poured pad, copper risers to rooftop condensers, and all equipment associated with Modbus communications and security. Avoided interrupted service on other clients’ data lines in under-construction space.

 Goldman Sachs, Greenwich, CT – Constructed trading floor business continuity site with 400+ workstations, N+1 redundant power, additional power, and data distribution. Met with town officials to shepherd project through approval process. Overcame density objections while complying with fire egress regulations. Repurposed previous tenant’s work to accelerate the build process.

 JP Morgan Chase, Greenwich, CT – Completed phased build-out of office space and support infrastructure, including installation of new UPS power to the data center, a new IT support area, rooftop chillers, and piping fit into challenging chases. Data center was live the entire time, even while crews jackhammered through the concrete walls of an award-winning pre-cast building.

 Gen Re, Stamford, CT – Led construction of a white-space data center for HQ buildings connected to a remote, stand-alone data center via fiber. Drove installation/construction of security system, BMS, audio-visual, redundant mechanicals, and life safety systems. Retrofitted older dry coolers with modern controls. Built grand lobby with Italian stone floors and Chinese tile mural.

 Viacom International Headquarters, New York, NY, $42M Budget – Project-managed construction of a high-end corporate headquarters (25 floors + radio station WLTW + corporate cafeteria built above an historic theater). Solved exhaust stack issue to create a supporting data center with generator and battery racks in the middle of the building 30 stories up. Managed early adoption and installation of fiber to the desktop to facilitate cutting-edge support of MTV and VH1. Prepared final financials and negotiated close-outs for client with GC and trades.

Career Timeline

WALBRIDGE, Detroit, MI – Field Manager / Technical Super, 08/2017 to Present

Team leader for data-center construction responsible for all field operations, team management, client communications, supply management, scheduling, constructability, change management, integration, and project delivery. Trusted to take point on the company’s ongoing expansion into mission-critical projects and successfully contributed to the first three data center projects.

  • Focus on adding value to the end result throughout the entire build cycle while over-delivering the technical requirements of the client, improving the professional relationship, and laying foundation for future engagements
  • Efficiently coordinate activities of QA/QC, technical, engineering, and installation services groups
  • Adopted Lean and Agile techniques and methods to streamline the fast-track build process in mission-critical environment

LINESIGHT, Boydton, VA – Consulting Project Manager / Owner’s Representative, 04/2016 to 07/2017

Provided directional oversight and drove completion of large-scale projects in the live operating environment. Invited by Microsoft management to join the Data Center Construction and Development (DCD) team.

  • Simultaneously managed multiple projects on five different campus data centers of various designs and logistics
  • Led cross-functionally at all levels to build relationships with clients, vendors, contractors, and inspectors


STRUCTURETONE MISSION CRITICAL, New York, NY – Construction Manager, 03/2015 to 03/2016

Transitioned from Pavarini to parent company STI to oversee large-scale data-center build-outs. Developed civil infrastructure and campus admin building on new build 34-mW campus for Microsoft from the ground up through commissioning and occupancy.

STRUCTURETONE – PAVARINI CONSTRUCTION, Stamford, CT – Project Manager / Superintendent, 03/2007 to 03/2015 Developed complex fit-outs, corporate HQs, labs, data centers, and banks. Supervised trades and labor while working with leadership team to deliver projects for major clients: Avon, JPMorgan Chase Hedge Fund Services, Goldman Sachs, Merrill Lynch, Lehman Brothers, Manhattan College, MetLife, Starwood Hotels, Fidelity, Knight Equity Markets, Thomson Reuters, and Praxair.

 A. PAPPAJOHN COMPANY, Stamford, CT – Project Manager, 04/2006 to 11/2006

Led teams of supers and trades to develop a condominium complex in Island Park, NY, and Stanwich Club renovations in Greenwich, CT. Within eight months, was recruited away by StructureTone to help handle the growing project load in CT/NY area.

MULLIGAN DESIGN AND CONSTRUCTION, Stamford, CT – Owner / Builder, 2001 to 2006

Provided design-build services for retail, commercial, and residential projects in the Fairfield/Westchester markets: The Pound Ridge Learning Center, Ridgefield School of Dance, and Aglietii Residence. Engaged local trades amid the fallout of 9/11.

TECHNOLOGY SOLUTIONS COMPANY, Chicago, IL – Consultant / Technical Writer, 1999 to 2000

Served on a team at Pfizer Pharmaceuticals to write user guides for their adverse reactions to drugs compliance database.

DATAVIEW, LLC, Mt. Kisco, NY – Partner, 1994 to 1999

Dotcom start-up that put financial analytics product MarketGaugeonline. Built the company’s first data center. Created presentations, website, and marketing materials. Recruited staff for company growth. Company is still thriving and growing.

 EARLY CAREER EXPERIENCE (see LinkedIn profile for more information)

  • LEHR CONSTRUCTION COMPANY, New York, NY – Project Manager / Owner’s Rep, 1987 to 1994
  • HERBERT CONSTRUCTION, New York, NY – Project Manager, 1987
  • MULLIGAN CONSTRUCTION, INC., New York, NY – Owner, 1984 to 1987


MA in Communications, Concentration in Science, Health, and Environmental Reporting, New York University, New York, NY

BA in Environmental Sciences, Stockton University, Pomona, NJ (achieved role as a County Planner Aide after graduation) Coursework (and fencing instruction) at Baruch College (CUNY), New York, NY (transferred)


LEED A.P. BD+C, U.S. Green Building Council, #10205449

OSHA 30 Certification