20'x20' concrete slab cost in Canada 2026-2027

When planning a concrete slab project, understanding the costs involved is crucial. Whether you want a simple slab for a garage or a heated driveway slab, prices can vary significantly depending on the features and location. This post breaks down the typical costs for a 20'x20' concrete slab in Ontario, Canada, covering areas from Ottawa to the Greater Toronto Area (GTA), Kitchener-Waterloo, and London. You will also learn what factors influence the price and what to expect when budgeting for your project.

Typical Cost Range for a 20'x20' Concrete Slab

A standard 20'x20' concrete slab usually costs between $8,000 and $13,000 in Ontario. This price range covers a basic slab with standard thickness, reinforcement, and finishing. The variation depends on several factors such as:

• Material prices: Cement, sand, gravel, and reinforcement steel costs fluctuate.

• Labour rates: Skilled labour availability and rates differ across regions.

• Site preparation: Excavation, grading, and soil conditions can add to the cost.

• Finishing options: Smooth, broom finish, or stamped concrete affect pricing.

  
  

For example, a slab poured in Ottawa might be closer to the lower end of the range, while in the GTA or London, prices tend to be higher due to labour and material costs.

Heated Driveway Slab Costs

If you want a heated driveway slab, expect the cost to rise significantly. Heated slabs include embedded heating elements or hydronic tubing to melt snow and ice during winter. For a 20'x20' heated concrete slab, prices range from $20,000 to $26,000 in Ontario.

This higher cost includes:

• Heating system installation: Electric cables or hydronic pipes embedded in the slab.

• Additional electrical or plumbing work: Connecting the heating system to your home’s power or boiler.

• Increased labour and materials: More complex installation requires skilled contractors.

  
  

Heated slabs offer convenience and safety benefits, especially in regions with heavy snowfall like Ottawa and Kitchener-Waterloo.

Factors Affecting Concrete Slab Costs

Understanding what drives the price helps you plan better. Here are the main factors:

Size and Thickness

While this post focuses on a 20'x20' slab, thickness matters. Standard slabs are usually 4 inches thick, but garages or driveways may require 5 to 6 inches for durability. Thicker slabs use more concrete and reinforcement, increasing costs.

Site Conditions

If your site requires significant grading, excavation, or soil stabilization, expect higher costs. Rocky or uneven terrain demands more preparation work.

Reinforcement

Concrete slabs often include steel rebar or wire mesh to improve strength. The type and amount of reinforcement affect the price.

Finishing and Design

Basic smooth finishes cost less than decorative options like stamping, staining, or exposed aggregate. These add aesthetic value but increase labour and materials.

Location and Accessibility

Urban areas like the GTA may have higher labour costs and permit fees. Remote or hard-to-access sites can also increase expenses.

What’s Included in the Cost?

When you receive a quote, check what is included. A typical concrete slab cost covers:

• Concrete materials and delivery

• Labour for pouring and finishing

• Reinforcement materials

• Basic site preparation (grading and excavation)

• Permits and inspections (sometimes)

  
  

Heated slabs include additional costs for heating components and electrical or plumbing work.

Tips to Manage Your Concrete Slab Budget

• Get multiple quotes: Compare prices from several contractors in your area.

• Plan site preparation: Clear and level your site beforehand to reduce labour costs.

• Choose standard finishes: Avoid decorative finishes if budget is tight.

• Consider slab thickness carefully: Don’t overbuild; consult a professional for the right thickness.

• Ask about warranties: Quality workmanship can save money in the long run.

  
  

Summary

A 20'x20' concrete slab in Ontario typically costs between $8,000 and $13,000, depending on materials, labour, and site conditions. If you want a heated driveway slab, expect to pay $20,000 to $26,000 due to the added heating system and installation complexity. Knowing these costs and factors helps you plan your project realistically and avoid surprises.