Every year in Calgary, hundreds of demolition and excavation projects take place in proximity to established neighborhoods, bustling commercial districts, and rapidly developing new communities. The responsibility of safeguarding adjacent buildings and public spaces during these operations is not just a professional standard-it is a legal obligation meticulously outlined in the National Building Code (NBC) Section 8.2.2.2. For homeowners, builders, and developers, awareness and compliance with these requirements are crucial. Proper protection of adjoining property during excavation is vital to prevent costly damages, ensure public safety, and uphold the integrity of Calgary’s built environment.

Understanding the Legal Responsibility: NBC Section 8.2.2.2

Section 8.2.2.2 of the National Building Code serves as the benchmark for protecting adjoining properties during excavation and demolition. The code stipulates:

  • If the safety or stability of any adjoining property may be endangered as a result of excavation, adequate means of support-such as underpinning, shoring, and bracing-must be provided. This is to prevent damage or movement of any part of the adjoining structure and eliminate hazards to the public.

Failing to comply with this section is not merely a technical oversight; it can have profound legal, financial, and reputational consequences. Lawsuits, stop-work orders, and reworking foundations at great expense are just a few of the risks faced when these protective obligations are neglected.

Why Protection of Adjoining Property Matters

Excavation is one of the most disruptive phases of any construction or demolition project. The process involves removing earth, often near property lines or underfoot of existing structures, to set foundations, basements, or service routes. Without proper precautions, excavation can cause:

  • Soil movement-leading to subsidence or shifting of neighboring foundations.
  • Cracking or settlement-in walls, concrete pads, driveways, and sidewalks.
  • Collapse risks-particularly for older buildings with shallow or unreinforced foundations.
  • Hazards to the public-such as open trenches, unstable ground, falling debris, or blocked right-of-ways.
  • Delays, legal action, or loss of insurance coverage-if requirements are not met.

Recognizing these risks, the NBC and the City of Calgary require rigorous assessment, detailed permits, and technical controls throughout the excavation process.

Who Is Responsible?

The duty to protect adjacent property typically falls upon the party who initiates the excavation-most often, the owner, developer, or builder, and by extension their contractors. However, all those involved in the planning and execution of the work bear responsibility for compliance with codes, local bylaws, and engineering best practices.

Underpinning, Shoring, and Bracing: The Protectors of Property

To protect neighboring buildings during excavation, the NBC prescribes several engineering controls:

  • Underpinning: Strengthening or reinforcing the existing foundations of an adjacent structure, often by extending the foundation’s depth or breadth beneath ground level.
  • Shoring: Installing temporary supports-such as vertical posts, sheeting, or hydraulic systems-to support earth walls and prevent collapse or soil slippage.
  • Bracing: Providing rigid frames or supports that stabilize shoring or underpinning systems, preventing movement from pressure, vibration, or unexpected ground shifts.

The choice, design, and implementation of these controls depend on multiple factors:

  • Soil type and stability-clay, sand, silt, gravel, fill, or bedrock.
  • Water table and drainage conditions-high groundwater or poor drainage increases risk.
  • Depth and footprint of excavation relative to property lines.
  • Type, age, and condition of adjacent buildings-older or lightly built structures are more vulnerable.
  • Proximity to public infrastructure-streets, sidewalks, utility lines, and other essential services.

Professional Assessments and Design

The National Building Code and City of Calgary both require a geotechnical engineer to assess the site and soil conditions, especially where neighboring properties could be affected. In more complex scenarios, or where substantial risks are present, a structural engineer may also be required to develop a customized protection plan. Their design will address:

  • Required depth and extent of underpinning
  • Best shoring systems (soldier piles, sheet piling, soil nail walls, etc.)
  • Strategic bracing to accommodate dynamic loads
  • Monitoring and triggering thresholds for intervention

The Permit Landscape in Calgary

To ensure orderly and safe excavation around the city, Calgary’s municipal authorities enforce a comprehensive permitting process. This process is designed to protect not only property owners but also the public and city infrastructure. Understanding which permits are necessary, and how to obtain them, is essential for homeowners, builders, and developers alike.

Key Permits Required for Excavation and Demolition

  • Excavation Permit: Required whenever the project involves breaking or digging within municipal road right-of-way. The permit application ensures proper planning for public safety, site restoration, and the protection of underground utilities.
    • Applications are submitted through the City of Calgary ePermits system.
    • Review timeframe: Standard applications-up to two business days. For work on new pavement (within two years), processing can take up to ten business days.
  • Indemnification Agreement: Before obtaining an excavation permit, certified contractors must sign an indemnification agreement, which:
    • Protects the City from liability
    • Ensures contractor work adheres to bylaws and standards
    • Mandates a two-year maintenance period post-completion
  • Utility Alignment Permit: If your project affects utility placement or disturbs rights-of-way serving city infrastructure, this six-month permit is mandatory.
  • Street Use Permit: Whenever part of a city right-of-way (such as a curb, sidewalk, or roadway) needs to be used exclusively during construction, this permit maintains public access and safety.
  • Hoarding Permit: For the storage of building materials or machinery on city property adjacent to the project. This prevents encroachment on pedestrian or vehicular access routes.

Permitting Process: Step-by-Step

Properly securing permits is as important as technical design. Here’s the recommended process:

  1. Conduct a Site Assessment: Hire a geotechnical engineer to evaluate the site, soil, and adjacent properties.
  2. Create a Protection Plan: Work with your engineers and demolition/excavation contractor to develop underpinning, shoring, and bracing details.
  3. Engage a Certified Contractor: Choose a team with a solid track record for safety and compliance. They must have an approved indemnification agreement on file with the City.
  4. Apply for Permits: Submit all required documentation through the ePermits portal-including technical reports, support system designs, insurance documents, and maintenance plans.
  5. City Reviews and Approves: The municipality reviews the application, seeks clarifications if needed, and issues permits when all criteria are met.
  6. Begin Work: Only once all permits are in hand may excavation and demolition commence.

This process is detail-intensive for good reason-each stage is designed to prevent harm and minimize risk for the broader community.

Cost Considerations for Permitting and Protection

The financial landscape for excavation and protection work extends beyond the immediate costs of labor and materials. There are multiple fee structures, including:

  • Non-Refundable Administration Fees-for processing permit applications.
  • Works Inspection Fees-to cover city inspection before, during, and after work.
  • Asphalt Rehabilitation and Pavement Degradation Fees-if the integrity of municipal roads is disturbed or compromised; these ensure the city can repair as needed.
  • Top Lift Paving Fees-for high-quality surface restoration, often required when extensive trenching crosses major roads or drives.
  • Engineering and Design Costs-associated with geotechnical studies and protection plans.
  • Construction and Materials-for underpinning, shoring, bracing systems, and their removal/disposal post-completion.
  • Insurance and Bonds-to protect against liabilities should damage occur in spite of best efforts.

Total costs can vary widely but are always lower than the price of legal actions, repairs to neighboring buildings, or city-imposed delays. For the most accurate estimate, consult with your demolition/excavation partner and review the City of Calgary’s fee schedules.

Timelines: From Permits to Completion

Project timing is a critical concern for every stakeholder. Two major factors control timelines:

  • Permit Processing: Typically, within 2 business days for standard excavation permits, or up to 10 business days if recent pavement is impacted. Unforeseen questions or missing documents can prolong approval.
  • Project Execution: Actual excavation and remediation timelines depend on complexity, soil/weather conditions, stakeholder coordination, and quick response to any issues detected during work.
    • Allow for additional time if shoring, underpinning, or other protections are required.
    • Implementing or adjusting protective measures can also affect schedules, especially during inclement weather or in challenging geotechnical situations.

Careful planning, early engagement with engineers and city officials, and open communication with neighbors can all help keep your project on track.

Site Assessment: Starting Off on the Right Foot

Before breaking ground on any excavation or demolition project, thoroughly assess both your own property and all those adjacent to the work. This due diligence is best performed by professionals with expertise in the local conditions and regulatory environment. A comprehensive assessment includes:

  • Soil Evaluation: Classify soil types, bearing capacity, and moisture content through boring, sampling, and lab analysis.
  • Structural Review: Examine the type, age, and condition of neighboring buildings’ foundations and superstructures.
  • Survey and Documentation: Record existing cracks, settlement, or other relevant damage in adjoining properties with time-stamped photography and written reports.
  • Utility Locates: Mark and map underground services such as gas, water, sewer, telecom, or power to prevent accidental disruption.
  • Stakeholder Identification: Note adjacent property owners, tenants, utility companies, and city agencies with interests in site safety.

Documenting these baseline conditions creates a point of reference in the event of complaints or claims. It also informs correct engineering solutions and reassures neighbors and insurance providers that risks have been anticipated and responsibly mitigated.

Professional Consultation: Why Experts Matter

Even seemingly small excavations can produce disproportionately large risks. Calgary’s cold winters, variable water tables, and history of fill or glacial soils mean unexpected movement is always a possibility. By involving geotechnical and structural engineers at the planning stage, project risks can be identified and mitigated early. Their input covers:

  • Evaluation of soil and groundwater conditions
  • Modeling of potential deformation or collapse under different excavation profiles
  • Design of bespoke underpinning, shoring, and bracing systems
  • Specification of monitoring instrumentation (such as inclinometers, crack gauges, or vibration sensors)
  • Legally defensible reporting for permit approval and insurance requirements

With the input of professionals, design solutions can be tailored to achieve compliance, minimize cost, and maximize neighbor and public confidence. They play a vital role in ensuring that even challenging sites are managed without incident.

Compliance and Documentation: Avoiding Pitfalls

All excavation and protection work in Calgary must comply with the NBC, Safety Codes Act, and applicable city bylaws.

  • Keep All Documentation On-Site: Building permits, engineering reports, site drawings, and proof of insurance should be accessible throughout the project.
  • Carry Out Regular Inspections: Both city inspectors and your own team should regularly review supports for integrity, sign of movement, water ingress, or unauthorized removal.
  • Update Plans as Needed: If conditions differ from site assessments or plans-such as unexpected soil instability-the engineering team should revise designs immediately and submit for re-approval if necessary.
  • Maintain a Safety Log: Log observations, incidents, and daily site conditions to provide a defensible record of care and due diligence.

During demolition and excavation-especially where protection measures are in place-a lower threshold exists for “stop work” by city officials. Rapid response to questions, and readiness to adjust based on real-time findings, is fundamental to a smooth and safe process.

Common Non-Compliance Issues to Avoid

  • Failure to install underpinning or shoring systems where required
  • Excavating deeper or closer to property lines than permitted
  • Commencing work before permit approvals are secured
  • Poor communication with neighbors or city inspectors
  • Ignoring signs of building movement or soil collapse

Preventing these issues requires rigorous attention to regulatory requirements and a commitment to ongoing expert supervision throughout the project timeline.

Communication: The Foundation of Good Neighbour Relations

Prior to commencing any disruptive work, communicate openly and transparently with all potentially affected neighbors. This is more than a courtesy-it is a strategic step in minimizing complaints, delays, or claims. Recommendations include:

  • Advance Notification: Provide written and verbal notice of planned works, outlining dates, impacts, and measures taken to protect their property.
  • Offer Contact Details: Supply a project manager’s phone number and email for questions or concerns.
  • Describe Support Systems: Tell neighbors what to expect regarding underpinning, shoring, and bracing, so they understand the rationale and limitations.
  • Provide Emergency Protocols: Communicate the plans and contacts for emergencies involving property movement or disturbance.
  • Regular Check-Ins: Particularly for long-duration work, periodic site visits with neighbors can build confidence and address issues early.

Building good relations with those nearby can be the difference between a project that proceeds on schedule and one mired in disputes.

Excavation Best Practices: Keeping Safety and Compliance Front and Centre

Beyond regulatory and engineering requirements, all excavation and demolition projects should follow a practical set of best practices to ensure success:

  • Use Certified and Experienced Contractors: Only hire firms with an established record of successful, compliant, and incident-free work.
  • Install Barriers and Signage: Clearly demarcate excavation boundaries with hoarding, fencing, and visible warning signs to keep the public and unauthorized persons away.
  • Monitor Environmental Impacts: Control dust, manage water pooling, and ensure stockpiled earth doesn’t block drainage or sightlines.
  • Stage Equipment Safely: Keep machinery off unstable ground and away from edges; avoid unnecessary vibration or dynamic loading near protected buildings.
  • Limit Excavation Size at Any One Time: Work in manageable segments, backfilling and removing supports only when surrounding soil and structures are deemed stable.
  • Record All Movements: Use photos and measurement equipment to monitor for signs of slumping, cracking, or other instability in both your own and neighbors’ buildings.

Respond Quickly to Issues

If movement or damage is observed at any time during the excavation process:

  • Stop work immediately.
  • Inform the site engineer and, if necessary, the municipal inspector.
  • Adjust or augment underpinning, shoring, or bracing as directed by professionals.
  • Keep neighbors informed of findings and the actions being taken.
  • Document every step of the process.

Swift and decisive action can prevent a minor concern from developing into a serious liability or project stoppage.

Special Considerations: Historic Structures and Dense Urban Environments

Working near heritage buildings, century homes, or in infill neighborhoods presents unique challenges when it comes to protecting adjoining properties. Often, older buildings have shallow rubble footings, unreinforced masonry walls, or have subsided over decades. In these cases:

  • Even minimal vibration can cause cracking or settlement-so shoring and underpinning must be extra robust.
  • Pre-existing damage and settlement must be documented with care (preferably with third-party engineering reports).
  • Customized or non-invasive underpinning solutions (such as micro-piles or low-vibration drilling) are often stipulated by heritage authorities or insurance providers.
  • Tighter access may require innovative shoring or materials staging.

Collaboration with city officials, heritage consultants, and specialty contractors is recommended when undertaking such challenging projects.

Case Studies and Real-World Examples

Understanding the importance of NBC 8.2.2.2 protections can be illuminated through real-world successes and failures:

Case Study #1: The “Sinking Wall” on 16th Avenue

A multi-storey infill development began excavating foundations next to a century-old duplex. Without thorough site assessment, shoring was under-designed. Within a week, cracks appeared in the neighbor’s brick wall. Work was halted, substantial underpinning was retrofitted, and insurance claims mounted to over $200,000. The lesson? Never underestimate the vulnerability of old buildings-professional engineering assessment is non-negotiable.

Case Study #2: Downtown Office Block Success

A downtown high-rise developer engaged geotechnical and structural engineers to design a soldier pile and lagging wall system for their deep excavation. Extensive monitoring detected a minor shift in the adjacent property, and additional bracing was added immediately. The result: Zero damage to neighboring structures, and a positive relationship established with all stakeholders.

Case Study #3: Residential Garage Gone Wrong

A homeowner opted to dig a deep garage foundation along the shared fence line with minimal shoring. Groundwater and rain caused the neighbor’s side yard to slump, damaging a patio. Lack of permits invalidated their insurance claim, costing the owner the full cost of repairs. The takeaway: Even small-scale work must be approached with the same rigor as large projects-permits and professional input always matter.

Frequently Asked Questions

What triggers the requirement for protection of an adjoining property?

Protection is required when excavation work-whether for demolition, new foundation construction, or service installation-creates any risk of endangering the stability or integrity of adjacent structures or public right-of-ways. The closer and deeper your excavation is to another structure, the more robust the protective measures must be.

Can my contractor handle engineering and permitting, or do I need to engage separate professionals?

Licensed, experienced demolition and excavation contractors will usually have relationships with qualified engineers and should handle permitting as part of their standard offering. However, you are ultimately responsible for ensuring all necessary expertise is engaged and documentation is submitted correctly.

What happens if I proceed without necessary permits and protective measures?

You risk stop-work orders, legal action, denial of insurance, and personal liability for damages caused to neighbors, city property, or the public. Moreover, you may face substantial remediation costs and possible fines.

How can I reassure my neighbors during excavation?

By being proactive: notify them in advance, document pre-existing conditions, communicate regularly, and provide them with contacts for both your contractor and the project manager. Outline steps being taken to protect their property and respond promptly to any concerns.

What is the difference between shoring and underpinning?

Shoring supports excavated earth (to prevent cave-in) or adjacent buildings temporarily, whereas underpinning reinforces and stabilizes the existing foundations of a neighboring building, often permanently. Both may be used together, especially in challenging or high-risk sites.

Checklist: Steps to Protect Adjoining Property During Excavation

  • Engage qualified demolition/excavation and engineering professionals
  • Conduct geotechnical and structural site assessment
  • Document pre-existing conditions of neighboring structures
  • Design bespoke underpinning, shoring, and bracing solutions
  • Apply for and secure all required permits (excavation, indemnification, street use, utility alignment, hoarding)
  • Install and maintain protective systems as designed
  • Communicate with adjacent property owners and the public
  • Monitor site and neighboring buildings throughout work
  • Respond immediately to any signs of movement or distress
  • Remove supports only upon engineer sign-off and city approval
  • Restore public right-of-way and neighboring properties as required
  • Maintain a record of all plans, inspections, and communications

Conclusion: Building for the Future, Safely and Responsibly

Excavation and demolition projects in Calgary are essential for progress-whether you are rejuvenating a vintage home, developing an infill lot, or building major commercial infrastructure. However, with that progress comes the unyielding responsibility to protect what exists nearby. By adhering to NBC Section 8.2.2.2 and its local implementation, engaging professional engineers, following best practices, securing all needed permits, and communicating openly with all affected parties, you uphold the safety, trust, and reputation of our city’s construction community.

At Kingsway Demolition & Excavation, our team brings decades of experience and unwavering commitment to protecting every neighbor, every building, every time.