Trip hazards on walkways are more than just a minor inconvenience—they represent a serious liability risk for homeowners and a genuine safety concern for anyone using your property. When interlock pavers become uneven, creating lips and height differences between stones, the risk of someone catching their foot and falling increases dramatically. At Interlock Experts, we’ve helped countless homeowners address these dangerous conditions through professional releveling services, restoring both safety and curb appeal to their walkways.

Understanding why walkways become uneven, how to identify trip hazards before they cause injury, and the proper methods for releveling interlock pavers can help you maintain a safe, beautiful property for years to come.

The Legal and Financial Risks of Uneven Walkways

Before diving into the technical aspects of walkway releveling, it’s crucial to understand the liability implications of ignoring trip hazards on your property. In Ontario, property owners have a legal “duty of care” to maintain their premises in a reasonably safe condition for visitors, delivery personnel, and even trespassers in some cases.

Homeowner Liability in Ontario

Under the Occupiers’ Liability Act, you as a property owner can be held responsible for injuries that occur due to hazardous conditions on your property—including uneven walkway surfaces. If a visitor, mail carrier, or guest trips and falls on your uneven interlock walkway, you could face:

Personal injury lawsuits seeking compensation for medical expenses, lost wages, and pain and suffering
Increased homeowner insurance premiums following a claim
Potential denial of coverage if the insurance company determines you were negligent in maintaining your property
Legal defense costs even if you’re ultimately not found liable

The financial impact of a single trip-and-fall injury can easily reach tens of thousands of dollars—far exceeding the cost of professional walkway releveling. More importantly, the peace of mind that comes from knowing your property is safe for family, friends, and visitors is invaluable.

When Does Unevenness Become a Trip Hazard?

Not every slight variation in paver height constitutes a dangerous trip hazard, but industry standards and legal precedents provide some guidelines. Generally, height differences of 1/2 inch (12-13mm) or greater between adjacent pavers are considered potential trip hazards. However, even smaller height differences can be problematic in high-traffic areas or where elderly individuals or children frequently walk.

You should consider professional interlock repair and releveling when you notice:

Visible “lips” where one paver sits noticeably higher than its neighbor
Areas where you can feel a distinct bump or drop when walking
Pavers that rock or move when stepped on
Sections of walkway that have clearly sunk or risen compared to surrounding areas
Water pooling on the walkway instead of draining properly

Common Causes of Uneven Interlock Walkways

Understanding why your interlock walkway has become uneven is the first step toward fixing the problem permanently. In the Ottawa region, we see several recurring causes of walkway settlement and heaving.

Tree Root Growth and Interference

One of the most common culprits behind uneven walkways in established Ottawa neighborhoods is tree root growth. As trees mature, their root systems expand outward in search of water and nutrients, often growing just beneath the surface of the ground. When roots encounter the base material beneath your interlock walkway, they can:

Push upward against the base, causing sections of the walkway to heave and create raised areas
Disrupt the compacted base material, creating voids that allow pavers to sink
Continue growing and expanding, causing progressive worsening of the problem over time

Large trees like maples, oaks, and willows are particularly problematic due to their extensive, shallow root systems. If your walkway runs near mature trees, root interference is likely contributing to any unevenness you’re experiencing.

Frost Heave and Freeze-Thaw Cycles

Ottawa’s harsh winters subject interlock walkways to tremendous stress through repeated freeze-thaw cycles. When moisture in the soil beneath your walkway freezes, it expands, pushing pavers upward. When it thaws, the soil contracts, often settling unevenly. Over multiple winter seasons, this process causes:

Gradual heaving of pavers, particularly in areas with poor drainage
Differential movement where some pavers rise more than others
Breakdown of the base material, reducing its ability to support pavers evenly
Shifting of edge restraints that normally hold pavers in place

For a detailed explanation of how heaving differs from settling, check out our guide on heaving vs settling pavers.

Poor Initial Installation

Unfortunately, not all interlock installations are created equal. Walkways installed without proper base preparation are virtually guaranteed to develop unevenness over time. Common installation deficiencies include:

Inadequate base depth (should be 6-8 inches of compacted granular material in our climate)
Improper compaction of base materials, leaving soft spots that settle under weight
Failure to establish proper drainage slope, causing water to pool and erode base material
Using inappropriate base materials that don’t provide stable support
Skipping edge restraints that prevent lateral paver movement

Soil Settlement and Erosion

Even with perfect installation, natural soil settlement can cause walkway unevenness over time. This is particularly common in:

Newer homes where construction has disturbed native soil
Areas where topsoil was recently added or grading was changed
Properties with clay-heavy soil that expands when wet and contracts when dry
Locations where underground water flow or poor drainage erodes base material from beneath pavers

The Professional Walkway Releveling Process

When you notice trip hazards developing on your interlock walkway, prompt professional attention can prevent the problem from worsening and restore safety to your property. Here’s what our interlock relaying and releveling process involves.

Initial Assessment and Diagnosis

The first step in any releveling project is a thorough assessment to identify the underlying cause of the unevenness. Our team examines:

The extent and pattern of settlement or heaving
Drainage conditions and water flow patterns
Proximity to trees and evidence of root interference
Condition of the existing base material
Original installation quality and edge restraint integrity

This diagnostic phase is crucial because it determines whether simple releveling will suffice or if more extensive base repair is needed for a lasting solution.

Paver Removal and Base Inspection

Once we’ve identified the problem areas, we carefully remove the affected pavers, typically working in sections to maintain the integrity of unaffected areas. Each paver is set aside for reinstallation—one of the great advantages of interlock is that the same pavers can be reused after releveling.

With pavers removed, we inspect the bedding sand and base material underneath. We’re looking for:

Voids or soft spots in the base that need filling and compaction
Evidence of water infiltration or poor drainage
Tree roots that need to be addressed
Contaminated or deteriorated base material that needs replacement

Base Repair and Preparation

Depending on what we find, base repair might involve:

Adding and compacting new granular base material to fill voids or low spots
Installing root barriers to prevent future tree root interference
Improving drainage by adjusting slopes or adding drainage channels
Completely rebuilding sections of base that have failed
Reinforcing or replacing edge restraints to prevent future movement

Proper compaction at this stage is critical. We use plate compactors and hand tampers to ensure the base is uniformly firm and will provide stable, long-term support for the pavers.

Screeding and Bedding Sand Installation

Once the base is properly prepared and compacted, we install a fresh layer of bedding sand—typically one inch thick. This sand is carefully screeded to ensure a perfectly level surface that will support the pavers at the correct height and slope for drainage.

The bedding sand serves several important functions:

Provides a smooth, level setting bed for pavers
Allows for minor adjustments to individual paver height
Accommodates the slight irregularities on the bottom of concrete pavers
Facilitates water drainage down through the paver system

Paver Reinstallation and Compaction

With the base and bedding sand properly prepared, we reinstall the pavers in their original pattern. Each paver is carefully positioned to maintain consistent joint widths and alignment with surrounding unaffected areas.

After all pavers are in place, we sweep polymeric sand into the joints to lock pavers together and prevent weed growth. Finally, we compact the entire area with a plate compactor fitted with a rubber pad to avoid damaging paver surfaces. This compaction:

Seats pavers firmly into the bedding sand
Ensures a level, uniform surface across all pavers
Activates the polymeric sand to begin binding
Eliminates any slight wobbling or movement of individual pavers

Final Inspection and Quality Assurance

After compaction, we conduct a final inspection, walking the entire releveled area to ensure:

No trip hazards remain—all pavers are within acceptable height tolerances
Proper drainage slope is maintained
Joint sand is properly installed and activated
The walkway is safe for immediate use

Prevention Strategies: Keeping Your Walkway Level

While some settling and movement is inevitable over time, proper maintenance and preventive measures can significantly extend the life of your walkway and minimize future trip hazards.

Maintain Proper Drainage

Water is the enemy of interlock stability. Ensure that:

Downspouts and eavestroughs direct water away from walkway edges
The walkway maintains its designed slope for water runoff
Joints remain filled with polymeric sand to prevent water from washing away base material
Adjacent landscaping doesn’t block drainage or direct water onto the walkway

Address Tree Root Issues Proactively

If your walkway is near trees, consider:

Installing root barriers during initial installation or releveling to redirect root growth downward
Choosing walkway routes that avoid large tree root zones when possible
Consulting with an arborist about root pruning options that won’t harm tree health
Monitoring for early signs of root heaving and addressing them before major damage occurs

Regular Maintenance and Inspections

Catching small problems early prevents them from becoming expensive trip hazards. We recommend:

Walking your walkway twice yearly (spring and fall) to check for developing unevenness
Refilling joints with polymeric sand when needed to maintain paver stability
Addressing any individual loose or rocking pavers immediately
Scheduling professional inspection if you notice any signs of settlement or heaving

Winter Care in Ottawa’s Climate

Our harsh winters demand special attention:

Use plastic shovels or snow blowers with rubber paddles to avoid damaging pavers and joints
Avoid using salt or harsh de-icing chemicals that can damage pavers and wash away joint sand
Clear snow promptly to prevent repeated freeze-thaw cycles from impacting pavers
Ensure good drainage so water doesn’t pool and freeze on the walkway surface

When to Call the Professionals

While minor maintenance like refilling joint sand can be a DIY task, walkway releveling is best left to professionals. The process requires specialized equipment, knowledge of base materials and compaction, and experience diagnosing the underlying causes of unevenness.

Attempting DIY releveling often results in:

Inadequate base repair that allows the problem to quickly return
Improper compaction leading to further settlement
Incorrect drainage slopes that create new problems
Damaged pavers from improper handling or compaction techniques

Professional releveling, while requiring an upfront investment, provides lasting results and actually saves money compared to repeated DIY attempts or dealing with liability issues from trip hazards.

Protect Your Property and Your Peace of Mind

Trip hazards on your interlock walkway aren’t just unsightly—they’re dangerous liabilities that put your family, visitors, and finances at risk. Whether caused by tree roots, frost heave, poor installation, or natural settlement, uneven pavers require professional attention to restore safety and prevent future problems.

At Interlock Experts, we’ve releveled hundreds of walkways throughout Ottawa and surrounding areas, addressing the underlying causes and delivering lasting solutions. Our experienced team understands the unique challenges of our climate and soil conditions, and we use proven techniques to ensure your releveled walkway remains safe and beautiful for years to come.

Don’t wait for a trip-and-fall injury to take action. If you’ve noticed uneven areas developing on your walkway, contact Interlock Experts today for a professional assessment. We’ll diagnose the problem, explain your options, and provide a detailed quote for releveling services. Protect your property, your loved ones, and your peace of mind with professional walkway releveling from Ottawa’s interlock experts.

Call us today or request a free quote through our website to schedule your walkway safety assessment.

Trip Hazards on Walkways: How We Relevel Interlock Safely