Basement Demolition Across the GTA — OCM Excavation

We handle basement demolition across the GTA. That means a clean interior strip-out of an old finished basement, or full structural removal where the old foundation comes out. Most basements we tear out cost $4,000 to $25,000 depending on scope, what’s behind the drywall, and whether the slab or footings come up with it. We’re an owner-operated crew, $2M insured, and we cover Toronto, North York, Scarborough, Etobicoke, Vaughan, Markham, Richmond Hill, Mississauga, Brampton, Oakville, and the rest of the GTA. Call 416-317-3090 for a same-week site visit.

When you actually need basement demolition

“Basement demolition” gets used loosely. Before we quote, we figure out which of three jobs you actually have. The price and the crew are different for each one.

Interior strip-out. The basement is finished and you want it back to bare concrete and joists. Drywall down, framing out, drop ceiling out, carpet and laminate up, old basement bathroom ripped out. Foundation walls and slab stay. This is the most common job. $4,000 to $9,000 for most GTA homes depending on square footage and whether there’s a bathroom and kitchen to disconnect.

Partial wall and slab removal. You’re keeping the basement but opening it up. That means knocking down interior partition walls, cutting out a section of slab for a new bathroom rough-in, or removing a load-bearing wall with a beam swap. This overlaps with renovation work and runs $6,000 to $15,000 depending on engineering and beam install.

Structural basement demolition. The old foundation comes out. This is what you need when an addition is going in, when a century-old rubble foundation has failed, or when the basement is being lowered and rebuilt from scratch. $10,000 to $25,000 for the demo portion alone, before any new foundation, drainage, or underpinning work begins. This job needs excavation equipment, shoring, and a clear sequence. Not a swing-hammer crew.

What we demo

• Drywall, plaster, lath, vapour barrier, and insulation
• Stud framing, soffits, bulkheads, and drop ceilings
• Subfloor, laminate, carpet, vinyl, and engineered hardwood
• Old basement bathrooms, including fixtures, tile, vanity, and shower pan
• Kitchenettes and bar areas, including cabinets, counters, and plumbing disconnects
• Partition walls and non-load-bearing interior walls
• Load-bearing walls with engineered beam replacement
• Concrete slab sections cut and removed with a walk-behind saw
• Old foundation walls (block, poured, or rubble) when the job calls for it
• Old footings and underpinning that’s no longer doing its job

Everything leaves the site in our bins. We haul to licensed transfer stations and keep the manifests. No piles left on your lawn, no dumpster sitting in the driveway for a month.

Why OCM vs a pure-demo crew

Here’s the part most homeowners learn the hard way. Basement demolition is almost never the whole job. Once the drywall and framing are out, you can finally see what the basement actually is. Nine times out of ten, what you see is a reason to do more work before you close it back up.

You strip a 1920s Toronto basement and find a rubble foundation weeping at the cove joint. You tear out a Scarborough rec room and the slab is cracked across the middle, rust staining from a rebar that’s gone. You open up a Vaughan basement and the headroom is 6’4″. You needed underpinning all along. You demo a Mississauga walkout and realize the back wall is the right candidate for a walk-up conversion.

A pure demolition crew finishes, packs up, and hands you the next problem. Then you spend two months finding a foundation contractor, a waterproofer, and an excavator. By the time they’re sequenced in, your basement has been open for half a year.

We do the demolition and the work that usually follows. Basement underpinning if you need height. Foundation waterproofing from the outside if the walls are leaking. Drainage and weeping tile replacement. Walk-up conversion if you’re building a separate entrance. One crew, one timeline, one number to call when something needs to be decided on the fly.

Process step-by-step

1. Site visit and scope walk. We come out, walk the basement with you, and ask what’s staying and what’s going. We check for the things that change price: asbestos-era materials, lead paint, knob-and-tube wiring, old HVAC that needs a licensed disconnect, structural walls.

2. Written quote with scope lines. You get a quote that lists what’s in and what’s not. No “demolition, $7,500” one-liners. If we’re hauling the old furnace, it’s a line. If we’re disconnecting the bathroom, it’s a line.

3. Permits and disconnects. If a structural wall is coming down, we pull a building permit and submit the engineer’s beam spec. Plumbing and gas get disconnected by licensed trades before demo day.

4. Containment and protection. Plastic at the basement stairs, runners on the floor up to the door, dust barrier on the main floor. Negative-air fan if there’s anyone living in the house during demo.

5. Demo and haul. Strip-out is usually 2 to 4 days. Structural demo with foundation removal is 5 to 10 days plus excavation. Bins on site, loaded daily, manifested to a licensed facility.

6. Hand-off or continue. If demo was the whole job, you get a clean basement and a final sweep. If we’re staying on for waterproofing, underpinning, or a related excavation, the next sequence starts the same week.

Permits, asbestos, and lead paint — what you should know

If your GTA home was built before 1990, your basement may have materials that need testing before demolition starts. Vinyl floor tile, mastic, pipe wrap, vermiculite insulation, and some popcorn ceilings can contain asbestos. Painted surfaces in homes built before 1991 can contain lead. Canada restricted residential interior lead paint in 1976 and exterior in 1991. We don’t guess on this. The tell is usually a chalky paint layer under the latex, or vinyl tile glued straight to the concrete with black mastic. We pause and recommend a third-party test if the materials look the part. Testing is a few hundred dollars and saves you from much bigger problems if a removal goes wrong.

Permits are usually only required when you’re removing a load-bearing wall, cutting structural slab, or taking out a foundation. Pure cosmetic strip-outs typically don’t need a permit in most GTA municipalities. Every city is different, and we confirm with the local building department before we start. We don’t demo first and ask questions later.

Frequently asked questions

How much does basement demolition cost in the GTA?

Interior strip-out is $4,000 to $9,000 for most GTA basements. Partial structural work with wall and slab removal is $6,000 to $15,000. Full structural demolition with old foundation removal is $10,000 to $25,000 before any new foundation work begins. The big variables are square footage, bathroom and kitchen disconnects, and whether load-bearing or foundation elements come out.

How long does it take?

A standard interior strip-out is 2 to 4 working days. Partial structural demolition with beam install runs 4 to 7 days. Full structural demolition with foundation removal is 5 to 10 days plus excavation. Permit pulls and engineering can add 2 to 6 weeks at the front of the project, depending on which GTA municipality you’re in.

Do I need a permit to demolish my basement?

Usually no for a cosmetic interior strip-out. Drywall, framing, flooring, and a basement bathroom typically don’t trigger a permit on their own. You do need a permit if you’re removing a load-bearing wall, cutting structural slab, taking out a foundation, or doing work that changes the structure. We confirm with your local building department before we start so there are no surprises.

Can you tell if there’s asbestos before you start?

We can flag suspicious materials like old vinyl tile, vermiculite, and certain pipe wraps. We can’t confirm without lab testing. If your home was built before 1990 and we see materials that fit the profile, we pause and recommend a third-party test. Sampling is usually $300 to $700 and turnaround is a few days. Asbestos abatement, if needed, is a separate licensed scope.

What’s the difference between basement demolition and basement underpinning?

Demolition is removal. Underpinning is structural. You’re lowering the basement floor and extending the foundation deeper to gain headroom. Most underpinning jobs start with a basement strip-out, so they’re often sequenced together. If you’re trying to get from 6’4″ to 8’2″ ceilings, you want underpinning, not demolition. We do both.

Do you do the waterproofing and foundation work after demo?

Yes. That’s the main reason homeowners hire us for the demo in the first place. Once the basement is stripped, we can see what’s really going on with the walls and slab. Foundation waterproofing, weeping tile, sump install, underpinning, and walk-up conversion are all in-house. You don’t need to find a second crew.

What cities do you serve?

The full GTA: Toronto, North York, Scarborough, Etobicoke, East York, York, Vaughan, Markham, Richmond Hill, Mississauga, Brampton, Oakville, Burlington, Pickering, Ajax. If you’re inside the GTA, we cover it. If you’re a bit further out, call 416-317-3090 and we’ll let you know.

Get a basement demolition quote

If you’ve got a basement that needs to come out, finished or structural or somewhere in between, we’ll come walk it. You get a real quote with scope lines, and we tell you straight whether demo is the whole job or just the first step. Same-week site visits across the GTA.

Call 416-317-3090 or request a free quote online. Owner-operated. $2M insured. 5-star rated on Google.