What's The Difference Between Underpinning and Bench Footing?

As property values continue to soar across the Greater Toronto Area, homeowners are increasingly looking to maximize their existing space rather than moving to larger homes. Basement lowering has become an incredibly popular solution, with two primary methods available: underpinning and bench footing (also known as benching). While both approaches can transform a cramped, unusable basement into valuable living space, they differ significantly in process, cost, and results.

For Toronto homeowners considering digging out their basement, understanding the differences between these methods is crucial for making an informed decision.

When you decide to create a full height basement for your home, there are two methods that can be used. Underpinning and Bench Footing, both of them are acceptable ways to create a full height basement, and both of them have their pros and cons. Creating a full height basement is a complex and expensive job, so you should understand the differences when you go over your options with your contractor.

Underpinning: The Full-Height Solution

What Is Underpinning?

Underpinning is a structural process that extends your home’s foundation downward to create additional headroom in your basement. This method involves excavating beneath your existing foundation walls in carefully sequenced sections, extending the foundation walls downward, and then digging out the central basement area to create a deeper, full-height space throughout the entire basement.

The Underpinning Process

Sectional Excavation: The contractor works in small sections (typically 3-4 feet wide), digging beneath the existing foundation to the desired depth.
Foundation Extension: Each section’s foundation wall is extended downward with new concrete.
Sequential Progression: Work proceeds around the perimeter in a calculated sequence to maintain structural integrity.
Interior Excavation: Once the perimeter is complete, the interior space is excavated to match the new depth.
New Floor Installation: A drainage system, vapor barrier, and new concrete floor are installed.

Advantages of Underpinning

Maximum Usable Space: Provides full ceiling height throughout the entire basement.
Higher Property Value: Generally adds more value to your home compared to benching.
Aesthetic Appeal: Creates a traditional, rectangular room without perimeter ledges.
Flexibility for Future Use: Allows for any configuration of rooms or living spaces.
Greater Ceiling Height: Can achieve higher ceilings than bench footing typically allows.
Better Long-Term Investment: Typically provides better return on investment over time.

Disadvantages of Underpinning

Higher Cost: Generally 30-50% more expensive than bench footing.
Longer Timeline: Usually takes 6-10 weeks for the structural work alone.
Greater Engineering Complexity: Requires careful structural planning and execution.
Structural Risk: If not properly executed, can potentially compromise home stability.
More Extensive Permits: May require more detailed engineering approvals in Toronto.

Bench Footing: The Perimeter Approach

What Is Bench Footing?

Bench footing (or benching) creates a concrete “bench” or ledge around the perimeter of your basement where the original foundation meets the new lower floor. Only the central area is excavated deeper, while the original foundation walls remain untouched. This creates a step or bench around the basement’s perimeter that’s typically 16-24 inches wide.

The Bench Footing Process

Central Excavation: The central area of the basement is excavated to the desired depth.
Bench Formation: The area where the original foundation meets the new lower floor is formed into a sloped concrete bench.
Drainage Installation: Proper drainage is installed beneath the new floor.
Floor Pouring: A new concrete floor is poured in the central lowered area.
Waterproofing: The entire system is waterproofed to prevent moisture issues.

Advantages of Bench Footing

Lower Cost: Typically 30-50% less expensive than underpinning.
Faster Completion: Usually takes 4-6 weeks for the structural work.
Less Structural Risk: Doesn’t involve modifying the existing foundation walls.
Simpler Engineering: Requires less complex structural calculations and approaches.
Easier Permitting: Sometimes faces fewer regulatory hurdles in the GTA.
Less Disruptive: Creates less noise and vibration during construction.

Disadvantages of Bench Footing

Reduced Usable Space: The perimeter bench reduces the floor area by approximately 15-25%.
Design Limitations: The bench creates obstacles for future layout configurations.
Aesthetic Concerns: Some homeowners find the bench visually unappealing.
Potential Furniture Placement Issues: The bench can limit where furniture can be placed.
Lower Potential Value Addition: May add less value to your home compared to underpinning.
Height Limitations: Might not achieve as much ceiling height as underpinning can provide.

Choosing Between Underpinning and Bench Footing

Budget Considerations

For many Toronto homeowners, budget is a determining factor when it comes to basement lowering:

Underpinning Costs: Typically $50-$80 per square foot in the GTA
Bench Footing Costs: Typically $35-$60 per square foot in the GTA

For a 1,000 square foot basement, this difference can translate to $15,000-$30,000 in additional costs for underpinning. However, this higher cost must be weighed against the increased usable space and potential property value increase.

Space Requirements

Consider how you plan to use your basement:

Choose Underpinning If: You need to maximize every square foot, plan to create a legal basement apartment, or need the space for large furniture or specific room layouts.
Choose Bench Footing If: You have a larger basement where losing some perimeter space isn’t critical, or if you’re primarily creating recreational spaces where the bench might actually be useful (home theater, exercise area, etc.).

Property Considerations

Your home’s specific characteristics may influence which method is suitable:

Age of Home: Older Toronto homes (pre-1940s) with brick foundations sometimes benefit from underpinning as it reinforces the existing foundation.
Soil Conditions: Areas with challenging soil conditions may favor one method over the other, based on engineering assessments.
Existing Foundation: Homes with foundation issues might benefit from the reinforcement that underpinning provides.
Neighboring Structures: In densely populated Toronto neighborhoods, proximity to neighboring structures might influence the feasibility of different excavation methods.

Timeline Factors

If time is a consideration, benching typically offers a faster solution:

Bench footing projects often complete 2-4 weeks faster than comparable underpinning projects.
This shorter timeline means less disruption to your household.

Long-Term Value

For many Toronto homeowners, the long-term investment perspective is important:

Underpinning is generally considered to add more value to your property, particularly in high-value neighborhoods.
Full-height basements appeal more to future buyers than those with perimeter benches.
If planning to sell within 5-10 years, the value difference may outweigh the initial cost difference.

Why Underpinning Is Popular in the GTA

Underpinning has become the preferred method for many Toronto homeowners for several reasons:

Toronto’s Real Estate Values: With Toronto’s high property values, maximizing usable space offers significant financial returns.
Basement Apartments: The high demand for rental units in Toronto makes creating legal basement apartments financially appealing, and underpinning provides the full-height space needed to meet building codes.
Small Lot Sizes: Many Toronto homes sit on compact lots with limited options for outward expansion, making basement development the only feasible way to gain significant additional space.
Aging Housing Stock: Toronto’s older homes often have very low basement ceilings (sometimes under 6 feet), requiring significant lowering to create usable spaces.
Cultural Shift: There’s been a cultural shift toward viewing basements as premium living spaces rather than mere storage areas, driving demand for full-height, well-designed basement spaces.

Hybrid Approaches: Getting the Best of Both Worlds

Some basement lowering contractors in Toronto offer hybrid approaches that combine elements of both methods:

Partial Underpinning: Underpinning only specific areas of the basement where full height is most needed.
Strategic Benching: Creating benches only in less-used areas while underpinning main living spaces.
Structural Variations: Using columns or other structural elements to create more nuanced solutions.

These hybrid approaches can sometimes offer cost benefits while maintaining most of the advantages of underpinning. A qualified basement lowering contractor can assess your specific situation and recommend the most appropriate solution.

Building Code and Permit Considerations in Toronto

When choosing between underpinning and bench footing, Toronto’s building regulations are an important consideration:

Ceiling Height Requirements: Toronto building code requires a minimum ceiling height of 6’5″ (1.95m) for habitable basement spaces in most cases.
Permit Complexity: Underpinning typically requires more detailed structural engineering plans and approvals.
Inspection Process: Both methods require inspections at key stages, but underpinning may require more frequent inspections due to its structural complexity.
Secondary Suite Regulations: If creating a basement apartment, additional requirements for egress windows, fire separation, and separate entrances apply.

Your basement lowering contractor should be thoroughly familiar with Toronto’s specific requirements and handle the permitting process for you regardless of which method you choose.

To Summarize

Bench-Footing is Quicker	Underpinning is Stronger
Bench-Footing is Less Expensive	Underpinning Costs More Money
Bench-Footing Bypasses Foundations	Underpinning Strengthens Foundations
Bench-Footing is the Thief of Space	Underpinning Maximises Space

Making the Right Choice for Your Toronto Home

Both underpinning and bench footing can transform your basement into valuable living space, but they offer different advantages and trade-offs. The right choice depends on your specific needs, budget, timeline, and property characteristics.

For maximum usable space and property value, underpinning generally provides superior results despite its higher cost and longer timeline. For budget-conscious homeowners or those with less stringent space requirements, bench footing offers a more economical solution that can still dramatically improve your basement’s usability.

When selecting a basement lowering contractor in Toronto, look for companies with extensive experience in both methods who can provide a detailed assessment of your specific situation. The right contractor will guide you through the decision-making process, helping you weigh the pros and cons of each approach as they apply to your unique circumstances.

Regardless of which method you choose, transforming your basement can significantly enhance your home’s functionality and value in Toronto’s competitive real estate market. By understanding the differences between underpinning and bench footing, you can make an informed decision that best meets your family’s needs and budget.

Want to learn more about your basement lowering option in Toronto? Contact Nusite Group today for a free consulkation and estimate.

What’s The Difference Between Underpinning and Bench Footing?