Noticing gaps between your paver stones? You’re not alone. As Ottawa’s premier interlock specialists, we see this issue regularly—especially after our harsh winter-spring freeze-thaw cycles. While small gaps might seem like a minor cosmetic concern, they can quickly escalate into costly structural problems if left unaddressed.

In this comprehensive guide, we’ll explain exactly why gaps form between pavers, how to identify whether it’s a serious problem, and what professional restoration looks like. Whether you’re dealing with a new patio showing separation or an older driveway with widening joints, understanding the root causes will help you make informed decisions about repairs.

What Causes Gaps Between Pavers?

Gaps between interlock pavers don’t appear randomly. There are several specific causes, each requiring different approaches to fix properly.

1. Joint Sand Erosion and Washout

The most common culprit is joint sand erosion. Traditional mason sand or even polymeric sand can wash out over time due to:

Heavy rainfall: Ottawa’s spring storms can be particularly aggressive, washing sand from joints into drainage systems
Improper drainage: If water pools on your pavers instead of draining away, it slowly erodes joint material
Power washing: While cleaning your pavers is important, aggressive power washing at too close a distance literally blasts sand out of joints
Snow removal: Shoveling and plowing can scrape joint sand away, especially if done repeatedly over multiple winters

When joint sand disappears, pavers lose the lateral support that keeps them locked together. This creates visible gaps and allows individual stones to shift independently—a recipe for further deterioration.

2. Ant Activity and Insect Damage

Believe it or not, pavement ants are a significant problem in Ottawa’s residential areas. These industrious insects:

Excavate sand from paver joints to create their underground tunnels
Deposit excavated sand on the surface (those small piles you see on your patio)
Weaken the base support beneath pavers by tunneling
Create voids that allow pavers to settle unevenly

Ant-related gaps often appear clustered in specific areas—wherever the colony establishes its network. You’ll typically see small mounds of sand near the affected joints, a telltale sign of insect activity.

3. Poor Initial Installation

Unfortunately, not all interlock installations are created equal. Installation shortcuts that lead to premature gaps include:

Insufficient joint filling: Contractors who rush may not properly compact and fill joints during installation
Wrong sand type: Using unsuitable sand that doesn’t lock pavers together
Inadequate compaction: Skipping proper plate compaction steps means joints never fully settle
Missing edge restraints: Without proper borders, perimeter pavers gradually creep outward

If your interlock developed gaps within the first year or two, poor installation is likely the root cause. Quality work from experienced contractors rarely shows significant joint separation this quickly.

4. Freeze-Thaw Cycles and Seasonal Movement

Ottawa’s climate is particularly hard on hardscaping. Our temperature swings cause:

Frost heave: Ground freezing and expanding pushes pavers upward unevenly
Seasonal settlement: Spring thaw allows base materials to settle and compact
Differential movement: Different areas of your patio or driveway shift at different rates
Ice expansion: Water trapped in joints freezes, expands, and gradually widens gaps

This is why many Ottawa homeowners notice gaps opening up each spring after winter. The freeze-thaw cycle is relentless, and even well-installed interlock requires periodic maintenance.

5. Base Layer Settlement and Erosion

Sometimes the problem isn’t at the surface—it’s underneath. Base layer issues that cause gaps include:

Inadequate base depth (should be 6-8 inches of compacted gravel for driveways)
Poor drainage causing base material to wash away
Tree roots disrupting the base layer
Underground water flow eroding foundation materials
Settling of disturbed soil (common in new construction)

When the base fails, pavers don’t just separate—they also become uneven, creating trip hazards and drainage problems.

How to Identify If Gaps Are a Serious Problem

Not all gaps require immediate professional intervention, but some warning signs demand quick action:

Minor concerns (monitor and schedule routine maintenance):

Gaps less than 3mm wide
Uniform spacing across the entire surface
No paver movement or rocking when walked on
Pavers remain level with each other

Serious problems (require professional repair):

Gaps wider than 5mm
Progressive widening over months
Pavers that rock, tilt, or shift when stepped on
Uneven height between adjacent pavers
Visible voids beneath pavers when you look into gaps
Water pooling in gaps or failing to drain
Multiple pavers sinking together (indicates base failure)

If you’re unsure, our team offers free assessments. We can determine whether you need simple joint refilling or more extensive interlock repair work.

Temporary vs. Permanent Fixes: What’s the Difference?

Temporary Band-Aid Solutions

Homeowners often attempt quick fixes that provide short-term cosmetic improvement but don’t address underlying issues:

Dry pouring sand: Simply sweeping regular sand into joints without proper compaction washes out within weeks
Wrong sand products: Using play sand, beach sand, or topsoil instead of proper jointing sand
Surface-only repairs: Filling gaps without checking for base problems or proper drainage
Skipping activation: Using polymeric sand but failing to properly activate it with water

These approaches might last a season, but Ottawa’s weather will quickly undo the work. You’ll find yourself repeating the same repair annually—or more often.

Professional Permanent Restoration

Proper gap repair addresses root causes and provides lasting results:

Complete assessment of why gaps formed
Base layer inspection and repair if needed
Drainage evaluation and correction
Professional-grade polymeric sand installation
Proper compaction and activation procedures
Edge restraint reinforcement
Ant treatment if insect activity is present

When done correctly by experienced professionals, joint restoration should last 5-10 years or more, even in Ottawa’s challenging climate.

The Professional Joint Restoration Process

Here’s what quality polymeric sand installation and joint restoration looks like:

Step 1: Inspection and Assessment

Before any work begins, we thoroughly evaluate:

Extent of joint separation
Paver stability and levelness
Base layer condition
Drainage performance
Signs of ant activity or other damage
Edge restraint integrity

This diagnostic phase determines whether simple re-sanding will suffice or if more extensive repairs are needed.

Step 2: Cleaning and Preparation

Proper preparation is critical for polymeric sand success:

Remove all debris, vegetation, and old joint material
Vacuum or blow out joints completely (at least 1.5 inches deep for driveways)
Ensure pavers are completely dry (moisture prevents proper sand compaction)
Clean paver surfaces to prevent polymeric sand staining
Verify joints are at least 1/4 inch wide (polymeric sand minimum requirement)

Step 3: Paver Releveling (If Required)

If inspection reveals uneven pavers, we perform interlock relaying:

Carefully remove affected pavers
Add or remove base material as needed
Re-compact the base layer
Add fresh bedding sand
Relay pavers ensuring proper slope and drainage

Trying to fill joints on unlevel pavers is pointless—the problem will recur quickly.

Step 4: Polymeric Sand Application

Professional-grade polymeric sand application involves:

Selecting appropriate polymeric sand for joint width and traffic type
Spreading sand evenly across the entire surface
Using a soft-bristle broom to sweep sand into all joints
Multiple passes to ensure joints are filled to within 1/8 inch of paver surface
Plate compaction to consolidate sand in joints
Additional sand application after compaction to fill any settling

Step 5: Activation and Curing

The final critical steps that DIY attempts often get wrong:

Thoroughly cleaning excess sand from paver surfaces before wetting
Fine mist application to begin polymeric sand activation
Controlled water application—enough to activate but not wash away sand
Proper curing time (typically 24-48 hours) before traffic or exposure to rain
Weather monitoring to avoid rain within the curing window

Timing is everything. Professional crews check weather forecasts carefully and plan installation windows when conditions support proper curing.

Preventive Maintenance: Keeping Gaps from Returning

Once joints are properly restored, these practices help maintain them:

Annual inspection: Check joints each spring after snowmelt
Gentle cleaning: Use moderate pressure when washing (15-degree spray tip, 12+ inches from surface)
Top-up as needed: Address small erosion spots before they become large gaps
Proper snow removal: Use plastic-edged shovels and avoid metal scrapers
Drainage maintenance: Keep gutters and surface drains clear to prevent water pooling
Ant control: Address insect activity promptly if you notice sand mounds
Edge protection: Monitor edge restraints and repair any separation from paver field

Think of joint maintenance like maintaining your home’s weather stripping—small efforts regularly prevent big problems later.

When to Call Professionals vs. DIY

Homeowners can handle some simple maintenance, but certain situations demand professional expertise:

Suitable for careful DIY:

Minor touch-ups on small areas (less than 20 square feet)
Recent erosion from a single heavy rain event
Pavers that remain level and stable
No underlying base or drainage issues

Call professionals for:

Widespread gaps across large areas
Uneven or rocking pavers
Recurring gaps that keep returning
Drainage problems or water pooling
Visible base layer damage
High-traffic areas like driveways
Premium installations you don’t want to risk damaging

Poor polymeric sand application can actually make problems worse—creating haze on pavers, incomplete bonding, or premature failure. When in doubt, professional installation pays for itself in longevity and proper results.

What It Costs to Restore Paver Joints Professionally

Investment in proper joint restoration varies based on several factors:

Surface area: Larger patios and driveways have volume-based pricing
Joint condition: Extensive cleaning and preparation increase labor
Base repairs: If underlying repairs are needed, expect higher costs
Access: Difficult-to-reach areas require more time
Material selection: Premium polymeric sand products cost more but perform better

As a rough guideline, simple polymeric sand restoration on a well-maintained surface typically costs a fraction of full replacement, while extensive repairs with releveling and base work naturally cost more. We provide free estimates that detail exactly what work is needed and why.

Remember: addressing gaps early almost always costs less than waiting until base failure occurs. What might be a simple re-sanding project today could become a complete relaying project if deferred too long.

The Bottom Line on Paver Gaps

Gaps between your interlock pavers tell a story—about installation quality, maintenance history, drainage performance, and environmental challenges. While small gaps are normal and manageable, progressive widening signals problems that won’t fix themselves.

The good news? Professional joint restoration is straightforward, cost-effective, and provides excellent long-term results when done correctly. The key is proper diagnosis of why gaps formed, addressing any underlying issues, and using professional-grade materials with correct installation procedures.

At Interlock Experts, we’ve restored thousands of square feet of paver surfaces across the region. We know exactly what causes joint failure in our local climate, and more importantly, we know how to fix it permanently. Whether your pavers need simple re-sanding or more comprehensive repair, our team has the experience and equipment to deliver lasting results.

For more detailed guidance on polymeric sand, check out our comprehensive polymeric sand Ottawa guide, which covers product selection, installation techniques, and common mistakes to avoid.

Ready to Restore Your Paver Joints?

Don’t let small gaps become big problems. Our team provides free, no-obligation assessments of paver joint condition, including:

Detailed inspection of joint gaps and paver stability
Diagnosis of underlying causes
Clear explanation of repair options
Transparent pricing with no hidden fees
Professional recommendations based on your specific situation

We serve all of Ottawa and surrounding areas, with particular expertise in handling the challenges our climate creates for interlock installations. Contact Interlock Experts today at (613) XXX-XXXX or request your free assessment online. Let’s keep your pavers looking great and performing properly for decades to come.

Gaps Between Pavers: Why They Happen (And How Pros Restore the Joints)