Power, Process and Industrial Expertise
We are deeply embedded in our chosen markets, with key competencies in the power, process and industrial sectors. Our resume of experience in these markets is an impressive list of successfully completed projects that cut across a variety of services, including maintenance, modifications, construction, fabrication, and related specialty services such as condenser, valve, turbine and radiological services. From nuclear and fossil plants to specialty chemical producers, Day & Zimmermann customers reap the rewards of shortened cycle capital projects, optimized operations and maintenance investments, and a safe, secure environment for all stakeholders.

Nuclear Power
Day & Zimmermann is the leading nuclear plant maintenance and modifications contractor in the United States, providing services to more than 70 of the nation’s 104 active commercial nuclear power plants. We have more than 35 years of deep industry knowledge and experience in the management of nuclear plant maintenance and modifications projects to support refueling outages and online support, as well as a full complement of related construction and other major projects. Day & Zimmermann is currently recognized by Engineering News-Record (ENR) as the #1 Operations & Maintenance Contractor in Power.

Our comprehensive portfolio of services to the nuclear industry include:

• Extended power uprates
• Control room renovations
• ISFSI construction
• Containment sump strainers
• Major piping modifications
• Plant security upgrades
• Feedwater heaters
• Condensate filtrate systems
• RWCU modifications
• Turbine retrofits

We also have the capability to manage and direct field engineering and work package planning, estimating, scheduling and cost tracking, project management, QA/QC and site access processing.

Day & Zimmermann is actively involved on many fronts to address nuclear industry issues and act as an advocate for the benefits of nuclear power through safe, cost-effective plant operations. We work with INPO, ANS, NEI, EPRI and numerous other industry organizations, along with the Building & Construction Trades, on initiatives around labor availability, skills certification and training.

Fossil Power
Day & Zimmermann is a leading provider of maintenance services to the fossil market with project work at more than 40 utilities and more than 250 operating units, including extensive system-wide/multi-site contracts. Our project experience includes all sizes, scopes and levels of complexity for maintenance, modification and construction activities. We routinely support both planned outages and emergency call-out outages and provide all disciplines of labor in order to self-perform all major workscopes.

We perform boiler maintenance, including associated ductwork and equipment, for both emergency and planned outages. We maintain all required weld procedures and stamp certifications to perform boiler work in accordance with applicable codes.  Boiler maintenance accounts for approximately 25-30% of our annual fossil volume and Day & Zimmermann is historically ranked among the top five users of boilermakers in the U.S. by the National Association of Boilermaker Employers (NACBE). We average approximately 1.3 million boilermaker hours annually, equivalent to 650 boilermakers on our payroll every work day of the year.

Day & Zimmermann's expert staff and project teams deliver a wide range of boiler services that extend beyond routine boiler maintenance to include major projects such as:

• Waterwall, slope and element replacement
• SCR construction
• Reheat and superheat header/element replacement
• Scrubber system modifications
• Control room modifications
• Low-NOx installations
• Feedwater heater replacement
• High-energy pipe replacement
• Air heater replacement
• Coal handling equipment
• Turbine retrofits
• DCS installation
• Condenser and heater retubing
• Precipitator rebuild
• Pipe installations
• Coal bunker reline
• ID and FD fan refurbishments
• Coal car dumpers