Office Administrator

CertainTeed has an exciting career opportunity for an Office Administrator based in Mississauga to join our dynamic team. This is a great chance to join a Top Employer and contribute to our growth and success.

We are seeking a proactive, detail-oriented Office Administrator to support plant operations and administrative functions. Reporting to the Plant Manager, this role plays a key part in ensuring smooth daily operations across HR, production, maintenance, engineering, and shipping. The ideal candidate will be highly organized, able to manage multiple priorities, and maintain a high level of professionalism.

In addition to core administrative duties, the Office Administrator will manage plant communications, file systems, and general office upkeep. This will be an employee facing role focused on also supporting and resolving employees inquiries related to payroll items and will coordinate engagement initiatives through the social committee. This role requires strong interpersonal skills and the ability to build effective relationships with internal teams and external stakeholders.

Key Responsibilities:

Administrative & Office Support

Manage incoming calls and maintain telecommunication systems.
Perform general administrative tasks: correspondence, filing, photocopying, organizing, and report generation.
Maintain plant communications via SGTVs and internal channels.
Manage office and plant supply inventory.

Payroll & Employee Support

Process full-cycle bi-weekly payroll for hourly/union employees using UKG/Kronos with accuracy and on time
Liaise with HR and payroll teams on employee lifecycle changes (hires, terminations, STD/LTD, etc.).
Maintain confidential information and training records.
Support onboarding, benefits administration, and employee engagement activities working collaboratively with HR Manager.

Finance & Systems

Code and route invoices using tools such as Medius; resolve PO discrepancies and GRIR issues.
Perform SAP data entry for production and inventory tracking.
Conduct monthly inventory cycle counts and raw material audits.
Upload and track shipments in In4.orm; resolve COGI issues promptly.

Compliance & Reporting

Prepare and submit month-end reports for the People Pillar.
Track and report safety data weekly and monthly.
Ensure audit compliance and maintain documentation for internal controls.

Qualifications

Post-secondary education in Business Administration or related field.
5–10 years of experience in an office administrator role, preferably in a manufacturing environment.
Proficiency in MS Office, SAP, UKG/Kronos, Medius, and In4.orm. or related systems
Strong communication, problem-solving, and multitasking skills.
High attention to detail and ability to maintain confidentiality.
Comfortable working in a dusty plant environment and wearing PPE as required.

Here’s what we do…

CertainTeed is a subsidiary of Saint-Gobain, one of the top 100 industrial companies in the world. Saint-Gobain employs approximately 18,000 people in North America and approximately 168,000 people in 75 countries world-wide. Saint-Gobain’s North American companies operate 145 manufacturing facilities in industries as diverse as industrial ceramics and containers, reinforcements and flat glass, abrasives, and building materials. We’re proud that Saint-Gobain North America was recognized by Top Employers institute as one the best workplaces in North America & Canada.

For 113 years, CertainTeed has been synonymous with quality, trust, innovation, and service. Our team designs, manufactures and distributes materials and solutions in the construction and building materials market. CertainTeed’s broad product offering includes insulation, ceilings, roofing, siding, fence, railing, deck, exterior trim and gypsum board products. We provide comfort, performance and safety while addressing the challenges of sustainable construction, resource efficiency and climate change. Our offerings incorporate and promote the wellbeing for each of us and we are building a future where we collectively work together towards our core purpose to Make the World a Better Home.

Saint-Gobain is an inclusive and equal opportunity employer committed to providing reasonable accommodations throughout the recruitment process to applicants upon their request. This commitment is in accordance with the Accessibility for Ontarians with Disabilities Act (AODA).

What we offer…

In addition to a dynamic work culture that emphasizes dedication and effort, alongside enjoyable events and companywide activities, we also provide the following benefits that contribute to our Total Rewards Package:

We provide unique options to fit your unique lives! Our Total Rewards Program is customizable to accommodate your needs. Our menu of flexible options includes, but is not limited to:

• Excellent healthcare benefits package.
• Family Focus & Balance: Parental leave, paid time-off and Employee Assistance Program.
• Financial Security: Competitive RRSP, Company-funded DPSP (Deferred Profit-Sharing Plan) and Employee Stock Purchase Program (PEG).
• Volunteer Day off: Give back to the community – each employee has one paid day a year that they can use towards volunteering their time and effort with a registered charity. We are proud of our National Partnership with Habitat for Humanity