09 Sep How to Vet a Basement Underpinning Contractor in Toronto

Most advice about hiring an underpinning contractor tells homeowners to ask whether the company is “licensed and insured.”

That’s a reasonable start, but it is not enough.

A contractor can say they have insurance. They can send you a certificate. They can tell you a permit is being processed or that an engineer is involved.

The more useful question is:

What can you independently verify before you sign the contract or let excavation begin?

Toronto homeowners have access to public tools that can help confirm building-permit status, engineering credentials and, where applicable, WSIB standing.

VMB Group has completed more than 500 basement underpinning projects across the GTA over more than two decades. These are the checks we believe homeowners should be comfortable making on any contractor, including us.

Start With What You Can Verify Yourself

A polished website, five-star reviews and a professional-looking estimate can all help you evaluate a company.

But underpinning affects the foundation supporting your home, so some of the most important checks should go beyond marketing.

Before construction begins, you should understand:

• who is responsible for the design;
• whether the required permit has been issued;
• what professional engineering involvement applies to the project;
• whether appropriate insurance and workplace coverage are in place;
• exactly what the quotation includes;
• how unexpected site conditions will be handled.

Several of those items can be independently checked.

1. Check the Contractor’s WSIB Status Where Applicable

Ontario has compulsory WSIB coverage requirements for much of the construction industry, including many contractors, independent operators and construction businesses. There are, however, specific exceptions in the legislation, including certain home-renovation arrangements where a resident or family member directly hires a contractor.

That means the right question is not simply:

“Do you have WSIB?”

Ask the contractor what coverage applies to their business and request the information needed to verify their status.

A WSIB clearance shows that a registered business is in good standing with its reporting and premium obligations. Clearances are valid for up to 90 days and can be renewed.

If a clearance applies to the work, do not rely only on an old PDF or screenshot. Confirm the current status through WSIB.

It is also worth remembering that a WSIB clearance addresses workplace-insurance standing. It is not a substitute for asking for proof of commercial general liability insurance.

2. Verify the Professional Engineer When Engineering Is Required

Professional Engineers Ontario maintains a public directory where homeowners can search for PEO licence holders and confirm professional status.

But there is an important distinction.

Toronto does not state that every residential underpinning project must be fully designed by a Professional Engineer.

The City specifically requires professional engineering design and on-site review when, for example:

• the new foundation extends below an adjacent footing and falls within the soil’s angle of repose;
• the underpinning exceeds 1,200 mm of laterally unsupported height;
• the soil is clay or silt.

Toronto also states that, in all underpinning projects, professional engineering testing and reports are required at minimum during the first and last stages to pass inspections.

So rather than asking only:

“Do you work with an engineer?”

Ask:

“Who is responsible for the engineering on my project, and what professional reviews or reports will be required?”

If a P.Eng. has been named, you can verify that person through the PEO public directory.

VMB Group’s underpinning drawings and permits process coordinates these design and permit requirements before structural work begins.

3. Verify the Toronto Building Permit

Residential underpinning requires a City of Toronto building permit.

The City’s Building Application Status tool allows the public to search by address or application number and review information about a permit application and its status.

That gives homeowners a simple way to verify claims such as:

“The permit has been submitted.”

or:

“The permit has already been issued.”

Those two statements do not mean the same thing.

An application can be under review, on hold, ready for issuance or formally issued, among other statuses.

If the contractor says a permit has been filed, ask for the application or permit number and verify it independently.

And do not allow structural excavation to begin simply because someone says the permit is “almost ready.”

4. Look for Experience That Matches Your House

General renovation experience and underpinning experience are not interchangeable.

Excavating below an existing foundation introduces conditions that do not exist in a typical kitchen or bathroom renovation.

Even within underpinning, projects can vary significantly.

A detached home with a poured-concrete foundation is not necessarily the same project as:

• a semi-detached home;
• an older masonry or rubble foundation;
• a property with limited rear access;
• a house close to neighbouring foundations;
• a basement with significant water problems;
• a project involving a new walkout;
• a deeper-than-typical lowering project.

Ask for examples that resemble your property and proposed scope.

A contractor with relevant experience should be able to explain how the project conditions affect the work without pretending that every Toronto house follows exactly the same sequence.

For example, instead of asking:

“What’s your standard pin width?”

ask:

“How will the underpinning sequence for my house be determined?”

The answer should refer back to the drawings, structural conditions and site requirements rather than a single dimension used on every job.

5. Pay Attention to How the Quote Is Built

A low price is attractive.

A low price with a vague scope is much less attractive.

An underpinning quotation should make it reasonably clear what is included and what could become an additional cost.

Depending on the project, you may want clarity around:

• design and engineering;
• building permit;
• excavation;
• disposal of excavated material;
• underpinning and concrete work;
• temporary support where required;
• waterproofing;
• drainage;
• plumbing modifications;
• new slab construction;
• insulation;
• access;
• backfill;
• inspections;
• finishing exclusions;
• allowances for unexpected conditions.

The basement underpinning cost breakdown can help you compare what is actually included rather than comparing only the final totals.

An unusually low quote does not automatically mean something is wrong.

There may be a legitimate reason, such as a smaller scope, shallower excavation or a different structural approach.

For example, benching instead of full underpinning can produce a fundamentally different scope.

The concern is when two proposals appear to include the same work but one omits major items or leaves important responsibilities unclear.

6. Ask These Questions During the Site Visit

A contractor should see the property before making confident claims about structural scope and pricing.

During the visit, ask questions such as:

1. Who is preparing the design for this project?
2. Will a Professional Engineer be required, and at which stages?
3. Who applies for the building permit?
4. Will I receive the permit or application number so I can verify it?
5. How will the underpinning sequence be determined for this house?
6. How will nearby or shared foundations affect the work?
7. What excavation protection will be required?
8. What happens if the actual soil differs from what was expected?
9. What happens if the existing footing is different from the drawings or assumptions?
10. What is included in the quoted price and what could become a change order?
11. Can you provide proof of insurance and applicable WSIB information?
12. Can you show a completed project with conditions similar to mine?

One of the most useful questions is:

“What happens if you uncover something different from what you expected?”

Underpinning involves an existing structure and conditions that are partly hidden until excavation begins.

A contractor should have a process for documenting the condition, stopping work where necessary, involving the designer or engineer when required and agreeing on any change in scope before continuing.

The basement excavation guide explains why existing footing conditions, soil and neighbouring structures matter once the basement is opened.

7. Watch for These Underpinning Contractor Red Flags

No single behaviour automatically proves that a contractor is unreliable.

But several warning signs together justify more questions before you commit.

They Want to Start Before the Permit Is Issued

Underpinning requires a Toronto building permit.

If structural excavation is being scheduled before the required approval is in place, ask for a clear explanation.

They Cannot Explain Who Designed the Work

The contractor should be able to identify who prepared the project drawings and explain what professional involvement applies to the project.

They Will Not Give You Information You Can Verify

Permit numbers, professional names, insurance information and applicable WSIB details should not be mysterious.

The Quote Is Just One Number

You do not necessarily need a price for every bag of concrete, but you should understand the scope you are buying.

They Promise There Will Be No Surprises

Existing foundations and soil can reveal conditions that were not visible before excavation.

A credible contractor should explain how unexpected conditions are handled, not pretend they are impossible.

They Cannot Explain the Sequence in Plain Language

You do not need to understand structural engineering.

But the contractor should be able to explain, in understandable terms, how excavation will proceed and how the house remains supported throughout the work.

They Pressure You to Sign Immediately

A structural project worth tens of thousands of dollars should withstand comparison, questions and document review.

8. Check the Permit Yourself Before Work Begins

Toronto’s Building Application Status service is particularly useful because it removes one of the easiest claims to verify.

If the contractor says:

“Your permit is approved.”

check.

If they say:

“It has been submitted.”

check.

If they give you a permit number:

check that it corresponds to your property and review the status shown by the City.

The tool is publicly accessible and supports searches using an address or application information.

A reputable contractor should not object to you independently confirming information about your own project.

9. Verify the Scope Before Comparing Prices

Two underpinning quotes that differ by thousands of dollars may not actually be quoting the same project.

Before deciding which is cheaper, compare:

• proposed lowering depth;
• underpinning versus benching;
• amount of foundation being altered;
• permit responsibilities;
• design responsibilities;
• waterproofing system;
• drainage;
• plumbing;
• slab;
• insulation;
• concrete specifications;
• disposal;
• access;
• restoration;
• exclusions;
• warranties;
• potential change-order items.

Price only becomes meaningful after the scopes are comparable.

If one contractor includes waterproofing, drainage and a new slab while another stops at structural concrete, the totals should not be compared as if they represented identical work.

10. Check the Company’s Work, Not Just Its Rating

Online reviews can help identify patterns, but star ratings alone do not tell you whether a contractor has completed projects similar to yours.

Look for completed work.

Ask what the property looked like before excavation and what was changed.

VMB Group’s gallery shows examples of completed projects, while its reviews provide homeowner feedback that can be considered alongside permits, project documentation and the contractor’s answers during your assessment.

No single source should make the decision for you.

The objective is to see whether the company’s claims remain consistent across:

documents + public records + past work + site assessment + written scope.

What Does a Well-Planned Underpinning Project Look Like?

The exact process varies by property, but a properly planned Toronto underpinning project generally moves through several distinct stages.

It may include:

1. site assessment;
2. existing-condition review;
3. design and drawings;
4. professional engineering involvement where required;
5. permit submission and approval;
6. preparation and excavation;
7. staged underpinning according to the approved sequence;
8. required reviews, reports and inspections;
9. waterproofing and drainage work where included;
10. slab and related basement work;
11. final inspections and completion.

Toronto requires the underpinning plans submitted for permit to show the proposed stages numbered in the sequence of work.

Project duration should be treated as project-specific.

Permit review, excavation depth, site access, unexpected conditions, structural complexity and the amount of basement work included can all affect the schedule.

If your goal is additional living space, the amount of basement lowering ceiling height you can realistically gain is another factor worth understanding before comparing proposals.

Ready to Compare a Real Underpinning Quote?

Verifying a contractor should not feel confrontational.

For a project involving the foundation of your home, questions about permits, design, insurance, scope and professional involvement are reasonable.

A contractor confident in the process should be comfortable giving you information you can independently verify.

VMB Group has completed more than 500 underpinning projects across Toronto and the GTA over more than two decades.

If you’re comparing quotes or trying to understand what your basement actually requires, request a free site assessment and bring your questions.

The goal is not to ask you to take our word for it.

It is to give you enough information to check the project for yourself.

Frequently Asked Questions

How Can I Verify a Toronto Underpinning Permit?

The City of Toronto’s Building Application Status tool allows you to search by address or application information and review the status of a building-permit application.

Ask your contractor for the application or permit number once they say the submission has been made, then verify it independently.

How Can I Check Whether an Engineer Is Licensed in Ontario?

Professional Engineers Ontario provides a public directory where you can search for PEO licence holders by name or licence number.

If a Professional Engineer is named on your project, check that person’s status directly through PEO.

Does Every Underpinning Project in Toronto Need a P.Eng. to Design It?

Not necessarily.

Toronto specifically requires professional engineering design and on-site review in certain conditions, including work below an adjacent footing within the soil’s angle of repose, underpinning exceeding 1,200 mm of laterally unsupported height, and clay or silt soil conditions.

The City also states that all underpinning projects require, at minimum, professional engineering testing and reports during the first and last stages to pass inspections.

Does Every Toronto Homeowner Need a WSIB Clearance From the Contractor?

Not in every circumstance.

Ontario’s WSIB rules contain an exemption from the clearance requirement for certain home repair or renovation work where the contractor is directly retained by a resident, occupant or family member of the private residence.

Construction businesses may still have compulsory WSIB coverage obligations depending on how the business operates, so homeowners can ask the contractor what applies and verify relevant information.

How Long Is a WSIB Clearance Valid?

A WSIB clearance can remain valid for up to 90 calendar days and is renewable.

Should I Choose the Cheapest Underpinning Quote?

Not based on price alone.

First confirm whether the quotes include the same depth, structural method, permits, design, waterproofing, drainage, slab work, disposal and other major components.

A lower price can be perfectly legitimate if the scope is smaller or the proposed method is different.

How Much Deposit Should I Pay?

There is no single deposit percentage that determines whether an underpinning contractor is legitimate.

What matters is that the payment schedule is clearly written into the contract, tied to an understandable scope and project stages, and does not leave you paying disproportionately for work that has not yet been completed.

What Is the Most Important Thing to Verify Before Underpinning Starts?

There is not one credential that replaces every other check.

At minimum, confirm that:

• the required permit is in place;
• you understand who prepared the design;
• required professional involvement has been identified;
• insurance and applicable workplace coverage are documented;
• the scope and payment terms are clear;
• you understand how unexpected site conditions will be handled.

Underpinning safety depends on the entire process, not a single certificate.