Sean P. Mulligan headshot
Sean Mulligan – Mission Critical


SENIOR PROJECT MANAGER / OWNER’S REPRESENTATIVE – Proven track record in completing complicated builds of data centers, trading floors, financial centers, corporate headquarters, and laboratories. Problem-solver who successfully handles all project phases of challenging builds. Fluent in VDC, BIM, project management, and scheduling software. Team player who enjoys the challenges.


Data Center Projects

Facebook RVA Data Center, Richmond, VA – Owner’s Rep on the Infrastructure Construction Management (ICM) team. Project oversight in an advisory capacity. Interact with the General Contractor, Safety, Quality, Site and Facility Operations teams to construct & commission great structures.

Amazon AWS Data Centers, Columbus, OH – Field Manager for fast-track buildouts of 4 MW Data Hall “Pods”. Mechanical Gallery with ducted AHU’s, Electric Room with two lineups, two Gens on pads, two battery rooms, HACs, busduct, Fire Protection, EF’s, VFD’s

Microsoft BN9-13 Data Center, Boydton, VA – Managed Fit-Out, Integration, and Commissioning of 5 new data halls in three buildings covering 500,000 sq. ft. Over 70 MW of processing supported by 43 Generators, 160 External IDEC Air Handlers, over 25,000 pieces of equipment. LEED Gold project on very tight schedule and constrained site.

SoCal Edison Data Center, Irvine, CA – Leading a live-environment build of a fully commissioned, NERC-standard, highly-secured 132 rack Data Center within existing SCE property. Add 1.5 MW Generator; u-pgrade three existing Gens; Extend and Upgrade Paralleling Switchgear; MEPS and Life Safety; Integration via MOPs to every bit of live infrastructure.

Microsoft Data Centers, Boydton, VA – Oversaw out-of-the-ground construction of BN6 (32 MW in 4 AZ’s + Admin and Civil). Later managed multiple projects in five production data centers (over 100 MW). Worked with multiple teams to define project scope, bid to street, analyze, and level bids, award work and manage to close-out. Headed up teams to pinpoint and replace failing equipment.

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. Installed 2,000 AMP electrical services, a 1.5 MW generator, 130-ton air-cooled chillers, and all associated equipment.

Thomas Reuters, Valhalla, NY – Supervised expansion of an 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. Took care not to interrupt service on other clients’ data lines.

Goldman Sachs, Greenwich, CT – Trading floor business continuity site with 400+ workstations, N+1 redundant power, additional power, and data distribution. Met with town building officials to shepherd project through approval process. Overcame density objections while staying within fire egress regulations. Repurposed infrastructure from previous tenant to speed 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 – Oversaw 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 to work with modern controls. Labored over a grand lobby with Italian stone floors and Chinese tile mural.

Viacom, New York, NY – Project-managed construction of a high-end corporate headquarters (25 floors + radio station WLTW and the corporate cafeteria built above a 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 with GC and trades

Career Timeline

TLM Group, LLC, New York, NY – Senior Project Manager, 11/2019 – present

Representing Facebook with oversight of the RVA3 build. Interface with GC. Subs, Safety, and Ops teams to deliver a quality build.

WALBRIDGE, Detroit, MI – Field Manager / Integration Manager / Technical Super, 08/2017 to 11/2019

Team leader for Data Center construction responsible for all field operations, team management, client communications, scheduling, OFCI tracking, constructability, change management and project delivery. Helped win $400M of contracts for data centers.

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

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

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 a new build 34 MW campus for Microsoft from out of the ground through commissioning and occupancy.

STRUCTURETONE – PAVARINI CONSTRUCTION, Stamford, CT – Project Manager / Superintendent, 03/2007 to 03/2015

Developed complex fit-outs, corporate HQ’s, labs, data centers, and banks. Supervised trades and labor while working with management 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, 4/2006 to 11/2006

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

MULLIGAN DESIGN & 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 trade resources as needed to get a great job done.

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 MarketGauge online. Built the company’s first data center (a very DIY affair!). Created presentations, website, and marketing materials. Recruited staff for company growth. Company is still thriving and growing.

LEHR CONSTRUCTION COMPANY, New York, NY – Project Manager / Owner’s Rep, 1987 to 1994

Led large commercial buildouts in New York City, Chicago, Delaware, and New Jersey. Responsible for budgets up to $40M, scheduling, interfacing with all professionals, client satisfaction, full documentation, and project success. Clients included Viacom International, MTV Networks, Showtime, Katz Communications, Christian Dior, Chanel, Calvin Klein, The Trump Organization, Singapore Airlines, Wang, Squibb, Atlantic Bank, Macmillan Publishing, and Digital Equipment.

HERBERT CONSTRUCTION, New York, NY – Project Manager, 1987

Responsible for a half-dozen luxury residential projects on Park Avenue, River House, Trump Tower, and Museum Tower. Oversaw site supervisors and trades and met with clients and architects to iron out situations. In the office, performed pre-construction and reviewed all contracts and billing documents. Learned the good, the bad, and the ugly of NYC construction dynamics.

MULLIGAN CONSTRUCTION, INC., New York, NY – Owner, 1984 to 1987

Ran a successful “fast growth” family contracting company providing consulting and contracting services to demanding architects, designers, and clients. Diverse projects included high-end residences, townhouses, doctors’ offices, high-rise offices, and retail stores.



MA in Communications, New York University, New York, NY

BA in Environmental Sciences, Stockton University, Pomona, NJ

Baruch College (CUNY), New York, NY (transferred)




OSHA 30 Certification