Add Height to Your Basement: Underpinning vs. Benching

Many older homes have basements with low ceilings, often under 6.5 feet. This limits their use as living areas and reduces the home’s market appeal. Two common methods for increasing basement height are underpinning and benching. Both involve basement lowering, but the techniques, costs, structural impact, and outcomes differ. If you’re considering digging your basement deeper, understanding benching vs underpinning is necessary to make an informed choice.

What Is Basement Underpinning?

Underpinning involves extending your existing foundation walls downward. This method lowers the entire basement floor while supporting the house above. It’s more invasive and labor-intensive than benching but results in a flat, open floor area with maximum usable space.

What is underpinning basement work used for? Primarily, it’s chosen when:

• You want to achieve full ceiling height (usually 8+ feet)
• You need structural reinforcement
• You plan to finish the basement into a legal rental unit
• You want to expand livable square footage without changing the home’s footprint

The process includes the following:

1. Excavation in sections (usually 3-foot-wide segments)
2. Pouring new footings below the existing foundation
3. Extending foundation walls down to the new depth
4. Adding drainage and waterproofing systems
5. Pouring the new basement slab

This phased approach ensures the house remains supported throughout the process. Underpinning is time-consuming and costly but structurally sound when properly executed. For those seeking expert support with underpinning, House Renovations offers specialized basement modification services.

What Is Basement Benching?

Benching (also known as bench foundation basement work) is a method that also lowers the basement floor, but instead of moving the foundation deeper, it creates a ledge or “bench” along the perimeter. The original foundation remains untouched. This ledge is formed by benching basement footings, which extend inward from the base of the existing foundation wall at a downward angle. The result is a tiered wall system.

Benching basement foundation systems are less expensive and less invasive than underpinning but have trade-offs:

• You lose some interior floor space due to the permanent bench
• The space may feel narrower or more enclosed
• The resulting ledge cannot be removed or used efficiently
• It’s less attractive to future buyers or renters

Benching is often used when:

• Budget constraints prevent underpinning
• The home doesn’t require major structural upgrades
• The lowered basement is intended for storage, laundry, or recreational use (not legal occupancy)

Bench Footing vs Underpinning: Structural Comparison

Bench footing vs underpinning represents two fundamentally different ways to handle load-bearing during basement lowering.

Why Homeowners Choose to Lower Basements

Increasing basement height through digging basement deeper is not only about comfort—it often supports major home goals:

• Creating a legal rental suite
  Many cities require 7.5–8 feet of finished ceiling height to classify a space as a dwelling unit.
• Increasing property value
  Finished basements add resale value, especially in urban markets where space is limited.
• Improving foundation health
  Older homes may benefit from a stronger foundation via basement underpinning.
• Waterproofing and drainage upgrades
  Excavation offers the opportunity to address dampness and poor drainage during the process.
• Avoiding horizontal expansion
  Lower basement work allows homeowners to gain square footage without affecting yard space or zoning setbacks.

Benching Basement Pros and Cons

Pros:

• Lower cost
• Faster project timeline
• Less disruption to the home’s structural system
• Useful for utility rooms, playrooms, or storage areas

Cons:

• Permanent ledge reduces open space
• May reduce basement's future usability
• Not suitable for legal living units in most areas
• Less appealing in real estate listings
• More prone to moisture retention due to shelf-like structure

Underpinning Pros and Cons

Pros:

• Full floor-to-ceiling height
• Clean layout without ledges
• Greater potential for return on investment
• Makes space legally rentable in most jurisdictions
• Structural reinforcement adds safety and durability

Cons:

• High cost (often $60,000–$120,000+)
• Requires permits, inspections, and engineering plans
• Lengthy construction period
• Higher risk if performed by inexperienced contractors

Cost Comparison

Both options come at significant expense. However, benching basement methods cost about 30–50% less than underpinning on average.

Your total budget will also depend on basement size, soil type, access to the property, depth of lowering, permit requirements, and contractor rates.

Engineering and Permits

Most municipalities require:

• Detailed structural drawings
• Engineering stamps
• Excavation and shoring plans
• Building permits
• Inspections at several stages

Homeowners must factor these requirements into their timeline and budget. Cutting corners on permitting or using unqualified contractors can lead to structural failure, fines, or legal issues. House Renovations has experience navigating these processes and can provide the necessary documentation and project management.

Choosing Between Benching and Underpinning

The decision between bench footing basement work and full underpinning depends on:

• Purpose of the space
  Will it be lived in or used occasionally?
• Budget
  Do you have the funds for full excavation, waterproofing, and foundation upgrades?
• Local regulations
  Does your city allow benching for legal suites?
• Timeline
  How soon do you need the space?
• Resale goals
  Will the finished basement increase your home’s value?

If you’re preparing for resale or want a high-end finish, underpinning usually yields better results. If you simply need more functional space for a lower investment, benching is often adequate.

Final Thoughts

When planning to lower your basement, the method you choose impacts cost, space, structural safety, and property value. Underpinning delivers maximum height and functionality but requires significant investment. Benching is more budget-friendly and less invasive but sacrifices floor area and design options. Both involve foundation modification and excavation work, so hiring experienced contractors is critical to avoid future issues.

For tailored advice, technical inspections, and cost-effective solutions, consider working with professionals like House Renovations who specialize in basement remodeling and installation across the Greater Toronto Area.