What red flags should I watch for when reviewing interlock contractor quotes in Vancouver?

Watch for quotes that skip base preparation details, lack drainage specifications, or seem significantly cheaper than others — these are the biggest red flags that indicate corners will be cut on the foundation of your project.

Base and Drainage Red Flags

Vague or missing base specifications are the most serious warning sign. Legitimate quotes should specify exact base depth (6-8 inches for patios/walkways, 10-12 inches for driveways), the type of granular material (typically 3/4-inch minus crushed gravel), and compaction method (plate compactor in 2-inch lifts). If a quote just says "gravel base" without depth or compaction details, the contractor likely plans to cut corners on the most critical part of the installation.

No mention of drainage is equally concerning in Metro Vancouver's wet climate. Proper quotes should specify surface slope (minimum 2% away from buildings), drainage pipe installation where needed, and how water will be managed. Contractors who don't address drainage in their quotes don't understand Vancouver's climate challenges and will likely create water problems that destroy your installation within 2-3 years.

Geotextile fabric omission is another red flag, especially in areas with clay soil (Surrey, Richmond, Delta, Langley). Professional installers know that fabric separation between the subgrade and base prevents soil migration and maintains drainage capacity over time.

Material and Installation Warning Signs

Recommending standard sand instead of polymeric sand shows the contractor doesn't understand Metro Vancouver's rainfall patterns. Standard sand washes out within weeks during our October-to-March rainy season. Any contractor suggesting regular sand to "save money" will cost you more in maintenance and repairs.

Missing edge restraint specifications indicate sloppy installation practices. Professional quotes should include snap-edge or aluminum restraints along all unconfined edges. Pavers without proper edge restraints spread and shift over time, especially under vehicle loads on driveways.

Unusually low pricing often means inadequate base depth, poor compaction, or substandard materials. If one quote is 30-40% lower than others, investigate what's being cut. Quality interlock installation in Metro Vancouver costs $15-30 per square foot for concrete pavers — quotes significantly below this range sacrifice essential elements.

Professional Standards Red Flags

No WorkSafeBC coverage is both a legal requirement and a liability risk. Every legitimate contractor in BC must carry WorkSafeBC coverage. Ask for their registration number and verify it online. Contractors without coverage are operating illegally and put you at financial risk if someone is injured on your property.

Pressure to sign immediately or "today only" pricing indicates unprofessional sales tactics. Legitimate contractors provide detailed quotes and allow time for consideration. Quality hardscaping is a significant investment that deserves careful evaluation.

Cash-only payment requests or demands for large upfront payments are warning signs. Professional contractors accept multiple payment methods and typically request minimal deposits (10-25%) with progress payments tied to completion milestones.

Technical Knowledge Gaps

Inability to explain base requirements when asked indicates lack of technical knowledge. Professional interlock installers should easily explain why specific base depths are needed, how compaction works, and why drainage matters in Vancouver's climate.

No mention of permits for retaining walls over 4 feet shows ignorance of BC Building Code requirements. Contractors who suggest "no one will know" or "permits aren't necessary" are encouraging code violations that create liability issues.

Dismissing strata approval requirements for townhouse or condo projects indicates inexperience with strata-governed properties. Professional contractors understand that strata approval is mandatory and help navigate the alteration agreement process.

Quality Control Red Flags

No reference to industry standards like ICPI (Interlocking Concrete Pavement Institute) guidelines suggests amateur installation practices. Professional installers follow established standards for base preparation, compaction, and installation techniques.

Unwillingness to provide references or examples of recent work indicates either inexperience or poor-quality results they don't want you to see. Legitimate contractors proudly share photos and references from satisfied customers.

Vague timeline estimates without consideration of weather windows show poor project management. Professional installers understand that base work and polymeric sand application require dry conditions, especially during Vancouver's rainy season.

Getting Better Quotes

Request detailed specifications including excavation depth, base material type and thickness, compaction method, drainage provisions, edge restraint details, and material brands. Ask about their WorkSafeBC coverage, insurance, and recent project references. Quality contractors welcome detailed questions and provide comprehensive answers.

Compare apples to apples by ensuring all quotes include the same scope — excavation, disposal, base preparation, materials, installation, cleanup, and warranty terms. The cheapest quote often becomes the most expensive when you factor in repairs and reinstallation costs from inadequate base preparation.

Need help finding qualified interlock contractors who understand Metro Vancouver's unique requirements? Vancouver Interlock can match you with experienced professionals from the Vancouver Construction Network who provide detailed, professional quotes and stand behind their work.