Key Takeaways
- A proper interlocking quote must specify excavation depth, base thickness, materials by brand and product name, drainage plan, edge restraints, polymeric sand, timeline, and warranty terms in writing.
- “Base preparation included” with no depth stated means there is no accountability for what actually goes in the ground.
- “Supply and install” with no material spec is not a quote. It is a blank cheque for the contractor.
- Items most often missing from cheap quotes: demolition, bin disposal, drainage engineering, and edge restraint specs.
- To compare two different-looking quotes, reduce both to cost per square foot using the same base spec. Then compare.
- No written warranty, no material names, verbal-only quotes – each of these alone is enough reason to walk away.
What a Proper Written Interlocking Quote Must Include
Before you even read the number at the bottom, check whether these items are present. Every single one of them. If they are not, the quote is incomplete and you are being asked to trust the contractor on details they chose not to write down.
Scope of Work
Not “driveway installation.” An actual description of the work – which surfaces, what is being removed, where the project starts and ends, any curb cuts or step work included or excluded. If it is not written, it is not in scope.
Excavation Depth
The single most important technical line item. Driveways in Ontario need a minimum of 8 to 12 inches of combined excavation. Patios typically need 6 to 10 inches depending on drainage conditions. No stated depth means no accountability for what goes in the ground.
Base Material and Thickness
Standard residential driveways in the GTA use compacted Granular A aggregate. The quote must state the material type and compacted thickness. Less than 6 inches of compacted Granular A on a driveway is undersized for Ontario conditions.
Drainage Plan
“Proper drainage included” is a phrase, not a plan. The quote must describe the actual solution for your lot – a slope, a catch basin, a channel drain, or a grading adjustment. Get it in writing.
Materials: Brand and Product Name
Permacon, Unilock, Oaks, Cambridge – each has distinct product lines with different thicknesses and load ratings. A generic description lets a contractor substitute a cheaper product without technically violating the contract. If it is not named, it can be swapped. For driveways, 80mm thickness is standard. 60mm is for patios and walkways.
Edge Restraint Specification
Edge restraints hold the entire surface together. Without them, pavers migrate outward over time and joints open up. The quote should specify the type – plastic spike-in, aluminium, or concrete border course. “Edge restraint included” is not a spec.
Polymeric Sand
Some contractors swap polymeric sand for regular sand to cut costs without telling homeowners. Regular sand washes out and allows weed growth. Polymeric sand sets firm and resists both. The quote should state it specifically – by product type if possible.
Demolition and Disposal
If there is an existing surface to remove, demolition and bin disposal must be itemised separately. This is the most commonly excluded line item in low quotes. Concrete removal in the GTA adds $3 to $6 per square foot on top of installation. If the quote does not mention it, ask directly.
Project Timeline
A specific start date or a clearly stated booking window with conditions, plus an estimated duration for the work. Verbal commitments are not enforceable. “We’ll start in May” needs to be in the document.
Warranty Terms
What is covered, for how long, and the process for making a claim. A quote that mentions a warranty without stating its terms is not offering you a warranty. It is offering you a word. For a full breakdown of what interlocking warranties should cover, read our interlocking warranty guide for Ontario homeowners.
The Line Items Most Cheap Quotes Leave Out
A quote can look complete on the surface and still be missing thousands of dollars of work. This is where the gaps usually live.
Demolition and Bin Disposal
A quote for a driveway replacement that does not include concrete demolition and a bin is not a complete quote. It is a partial scope. When the contractor arrives and the homeowner asks about removing the old surface, the answer is usually “that is extra.” Sometimes substantially extra.
Drainage Engineering
Basic grading away from the foundation is standard. But if your lot pools water, sits low relative to the street, or has clay-heavy soil – a proper drainage solution is part of the job. Catch basins, channel drains, and French drains all have real costs. If your lot has drainage issues and the quote does not address them, the surface being installed over that unresolved problem will fail. Clay soil is common across parts of Brampton, Mississauga, and Vaughan. If your property is in one of these areas, drainage is a conversation that must happen at the quote stage.
Edge Restraint Type – Not Just “Included”
Many cheap quotes list edge restraint as a line item without specifying what kind. Cheap plastic restraints are not the same as properly installed aluminium or a concrete border. On driveways especially, vehicle load and plowing stress the perimeter constantly. The type matters more than most homeowners realise.
Geotextile Fabric
A layer of geotextile fabric between the native soil and the aggregate base prevents fine soil particles from migrating up into the base over time. Not every project requires it. But on properties with soft, organic, or clay-heavy soil, it should be specified. Most cheap quotes omit it without mention.
Compaction Passes
The number of compaction passes between base layers is one of the biggest determinants of long-term performance. A proper installation involves multiple passes with a plate compactor between lifts of aggregate. One pass is not three passes. This almost never appears in a quote, but you can ask for it in writing. The answer tells you whether the process is consistent or improvised on the day.
What Vague Language in a Quote Actually Signals
Vague quotes are not an accident. The language is chosen because it protects the contractor from accountability, not because the details are hard to write down. Here is how to read the most common phrases.
“Base Preparation Included” – with no depth stated
This sounds thorough. It means nothing. If the contractor installed 2 inches or 10 inches, both are technically base preparation. Without a stated depth, there is no benchmark. The job can be done any way the crew decides on the day, and nothing in the contract says otherwise. When you ask a contractor to state the base depth in writing and they resist, that resistance is information worth having.
“Supply and Install” – with no material spec
Supply and install what, exactly? If the paver is not named, the contractor can install anything that fits a loose description. Cheaper products, thinner profiles, a different colour than what you discussed. None of these are technically violations if the contract only says “supply and install concrete pavers.” This is a documented pattern in GTA interlocking disputes.
“Industry Standard Base”
There is no single universally enforced standard for residential interlocking base depth in Ontario. This phrase gives a contractor room to do whatever they consider standard – which may be considerably less than what your property requires. Ask them to define it in inches.
“Warranty Provided”
A warranty without terms is not a warranty. For how long? What does it cover settling, drainage failure, edge restraint movement? What is the claim process? If the quote says “warranty provided” and nothing else, ask for the terms in writing before you sign anything.
Red Flags That Should Stop You From Signing
Some things do not need a full explanation. A single red flag might be explainable on its own. Multiple from the same contractor is a pattern worth taking seriously.
Stop and ask questions if you see any of these
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Verbal quote only. Nothing in writing. If it is not on paper, it does not exist legally or practically.
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No WSIB mentioned. Residential interlocking in Ontario falls under WSIB Class C (Rate Group 190). Any properly registered contractor carries it. Ask for the clearance number and verify at wsib.ca before work begins.
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No written warranty, or warranty mentioned without terms. A warranty without scope, duration, and a claims process is a word, not a commitment.
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Materials not specified by name. “Grey paver, 60mm” is not a spec. A brand and product line is a spec.
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Cash only, no paper trail. No receipt. No recourse. Full stop.
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Pressure to sign today. “This price is only good until Friday” is a sales tactic, not a scheduling reality. A contractor who cannot hold a quote for 48 hours while you verify details is not worth hiring.
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Quote dramatically lower than all others. If two quotes are around $19,000 and one is $11,000 for the same scope, the gap lives in the base, the materials, or work that has been omitted entirely. That is not a deal. That is missing scope.
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No physical business address or traceable registration. Google the company. Check the Ontario Business Registry. If they cannot be found, they cannot be held accountable.
Already thinking about how to vet contractors beyond the quote? Our guide on how to choose an interlocking contractor in the GTA covers WSIB, insurance, deposit expectations, and what a proper contract looks like from start to finish.
How to Compare Two Quotes That Look Very Different on Paper
You have a $14,500 quote and a $21,000 quote. Both say roughly the same thing on the surface. Here is how to figure out what you are actually comparing.
Step 1 — Reduce Both to Cost Per Square Foot
Divide the total price by the square footage being installed. If Quote A is $14,500 for 600 sq ft, that is $24.17 per sq ft. If Quote B is $21,000 for the same 600 sq ft, that is $35.00 per sq ft. Now you have a common basis for comparison. Check our 2026 GTA interlocking cost guide to understand what different price points actually reflect in terms of specification and scope.
Step 2 — Match the Specs Side by Side
Look at what each quote states for excavation depth, base material type and compacted thickness, paver brand and product name, edge restraint type, demolition and disposal included or excluded, drainage solution described or absent, and warranty terms stated or vague. If one quote specifies 10 inches of compacted Granular A and the other says “base preparation included,” you are not comparing two quotes. You are comparing a number to a specification.
Step 3 — Price the Gaps Separately
If one quote excludes demolition and the other includes it, find out what demolition costs and add it back. Once you adjust for scope differences, the “cheaper” quote often ends up costing more than the one that looked expensive at first glance.
Step 4 — Ask Both Contractors the Same Three Questions in Writing
Send these by email so you have the responses documented: What is the excavation depth and compacted base thickness for this project? What paver brand and product line are you quoting? Is demolition and bin disposal included in this price? The responses — or the absence of responses — tell you a lot about who you are dealing with.
What to Ask When Something Is Missing From the Quote
You do not need to be an expert to ask the right questions. You just need to ask them clearly and in writing. Here is language you can use directly with any contractor.
A contractor with a solid process will answer all of these without hesitation. The answers are part of what they are selling. A contractor who becomes defensive, vague, or says “don’t worry about it, we’ve been doing this for years” — take that seriously. It is information about what comes next.
Not sure if your quote covers everything it should?
We write quotes that specify every line item — excavation depth, base thickness, material brand, drainage plan, edge restraints, demolition, and warranty terms. No vague language. No surprises when work starts.