Over the last 30 years in Ontario, Ledcor has continued to grow and evolve and is now a leading provider of construction services across the province. From our early days building infrastructure and developing communities, to our more recent work in the heavy civil and mining, residential, and aviation sectors, we have always been driven by our commitment to safety, quality, integrity, sustainability, and success. We are seeking an experienced Senior Estimator to join our team in Oshawa, Ontario, supporting a major GO Transit infrastructure project.

This is a key leadership position responsible for overseeing all estimating activities, from conceptual budgeting and detailed cost estimates to competitive bid submissions and subcontractor procurement. Lead the preparation and coordination of comprehensive estimate packages, including quantity takeoffs, costing, subcontractor pricing, and bid submissions. Develop conceptual budgets, detailed estimates, cost studies, and competitive tenders for complex construction projects.

Review drawings, specifications, terms, conditions, and bid documents to ensure all project requirements are incorporated into estimates. Analyze outstanding RFIs and identify appropriate bidding strategies for complex project requirements. Perform quantity takeoffs for large-scale projects and oversee the quantity takeoff process, ensuring accuracy and completeness.

Lead subcontractor and supplier solicitation activities and evaluate submissions. Recommend subcontractors and suppliers for project award based on scope, pricing, capability, and risk assessment.



Take ownership of estimate accuracy by reviewing and validating all direct and indirect project costs.

Review construction schedules and execution strategies to ensure alignment with estimate assumptions and project objectives. Prepare bid clarifications and support proposal development for major projects. Provide mentorship, guidance, and technical expertise to junior estimators and cross-functional teams.

Serve as a subject matter expert on estimating-related requirements and best practices. Bachelor's Degree in Engineering, Construction Management, Quantity Surveying, or a related field. Proven experience working on large, complex, multidisciplinary construction or infrastructure projects.

Experience within transit, transportation, civil, heavy infrastructure, rail, or major public-sector projects is considered a strong asset. Strong proficiency with Microsoft Office Suite and industry-standard estimating software. Knowledge of Building Information Modeling (BIM) and model-based estimating is considered an asset.

Solid ability to interpret and analyze construction drawings, specifications, and contract documents. Comprehensive knowledge of construction costs, budgeting principles, and project scheduling. Strong relationship-building skills with internal teams, subcontractors, consultants, suppliers, and clients.

Site-based role in Oshawa, Ontario.



#Ledcor builds and maintains infrastructure in various industries including oil and gas, transportation, and mining. We’re experts in all infrastructure construction and maintenance related projects.

Our vast projects include: full-scale contract mining, earthworks, foundations, highways, bridges, roads, waterways and resources, airports, rapid transit, underground utilities, pipelines, independent power projects and site reclamation.

Employment Equity At

Ledcor we believe diversity, equity, and inclusion should be part of everything we do. All qualified individuals, regardless of race, color, religion, sex, national origin, sexual orientation, age, citizenship, marital status, disability, gender identity, Veteran status or any other identifying characteristic are encouraged to apply. We are committed to continuing to build on our culture of empowerment, inclusion and belonging.

For more information about Ledcor’s Inclusion and Diversity initiatives, please visit our I&D; page. We're a diversified construction company, made up of teams of people who are proven in their industries. All working to design, build, transport, operate, and maintain projects all over North America.

But we believe that projects are about more than concrete and steel. Partnerships with our employees, our communities, our contractors and clients. We believe in building trust in the places where we do business—whether that’s by engaging honestly, by giving back, by putting safety first, or by looking for smarter, more sustainable ways to get the job done right. #

📌 Senior Estimator, Infrastructure (Bowmanville)
🏢 Ledcor Group
📍 Bowmanville