Foundation Repair in ON, including Toronto, Mississauga & Brampton.

Sinking/Settling Concrete Floor Slabs

diagram of a repaired concrete slab floor

Concrete slab piers being used underneath a floor to help stabilize the floor permanently.

Notice how the piers can extend deep below the floor, extending until they reach competent supporting soils.

The Problem:

Your concrete slab floor is showing signs of sinking, sagging, or settling. Your floor may be cracking, or the walls may be separating from the floor below or ceiling above.

Telltale Signs:

How to Fix It:

Install a slab pier system underneath your concrete slab floor. These piers can extend down to strong supporting soils, ensuring long-term support.

floor crack repair quote in Orangeville

We can fix your cracked slab floors once and for all! Call us for a free floor slab repair quote today!

We serve Mississauga, Toronto, Brampton, Markham, Hamilton, Richmond Hill, Vaughan, Burlington, Oshawa, Oakville, St. Catharines, Barrie, Whitby, Kingston, Clarington, Newmarket, Peterborough, Kawartha Lakes, Caledon, Aurora, Georgina, Ajax, Pickering, Guelph and many nearby areas in Ontario.

Signs Of Slab Settlement

When a floor slab settles, the damage can manifest itself in many ways. Along with cracks in the concrete, the floors can separate from the walls as they sink downwards. Alternatively, the interior wall may be pulled down with the floor, instead separating from the ceiling. Walls can also pull away from other walls, and interior wall cracks can form -- commonly off the corners of interior doors.

(Click each photo to enlarge.)

Slab floor cracks showing in a Aurora home Large slab floor cracks in a Caledon home A floor slab separating from the wall in a Kawartha Lakes home. A partition wall separating from the floor in a Newmarket home.
a sinking floor leaving a large gap between the wall and floor in a Clarington home The ceiling and wall separating as the wall sinks with the slab floor in a Pickering home partition walls being pulled away from the foundation walls in a Guelph home. wall cracks along a doorway in a Whitby home.

What Causes A Concrete Floor Slab To Settle?

When a concrete floor settles, it can mean serious damage to your home. The causes of floor slab settlement are almost always due to the soils underneath being unable to support the weight of the concrete. They often accompany other foundation problems in your home.

The three most common causes of settling concrete floor slabs are as follows:

(Click for more information.)

Dry, cracking clay soils Drying/Shrinking Of Soils Under The Slab soil erosion Washout Of Soil Underneath The Slab A backhoe excavating a foundation Poor Compaction Of Foundation Fill Soils

Fortunately, there are fast, effective ways to address concrete slab floor settlement issues. if you would like a free foundation slab stabilization quote for your problem, call or e-mail us today!

Installing The Foundation Supportworks Slab Pier System

Foundation Supportworks Slab Pier System stabilizes the concrete floor slab in your home. It provides the best opportunity to relevel the floor and lift non-load bearing partition walls that may have settled along with the slab. To install our system, our contractor will take these six steps:

Coring the concrete of a concrete slab floor in Kingston

Preparing for Installation

Before the installation day, a representative from our company will have already inspected your foundation issue. At that time, a foundation repair proposal was put in writing.

Your foundation repair experts will use that proposal to map out the locations where the slab piers will be installed.

At the beginning of each slab pier installation, a small hole is cored through your concrete slab floor. This hole will create an access point for the slab piers that are about to be installed.


A three piece foundation slab bracket assembled underneath a concrete slab floor.

Position Slab Bracket

To give the slab pier something to "lift", a slab bracket is positioned beneath the concrete slab.

The Foundation Supportworks Slab Pier System uses a three-piece slab bracket that is assembled underneath your concrete floor, allowing for a much smaller hole to be cored in your concrete slab. Additionally, this larger bracket reaches across more area along your floor, creating a more even distribution of weight.


Driving foundation piers into the floor in St. Catharines.

Install Steel Tubes

Steel tubes are hydraulically driven down through the bracket to the competent soils beneath.

These steel tubes are the real strength of the foundation pier system -- and are responsible for transferring the home weight to strong supporting soils.

To prevent corrosion, Foundation Supportworks has slab piers available that are designed using galvanized steel. This ensures the quality and long-lasting strength of your slab pier system.


Using steel slab piers to transfer the weight of the concrete slab to the soil beneath in Barrie.

Transfer Slab Weight To Soil

The weight of the concrete slab is transferred through the piers to the load-bearing strata underneath your home.

As the system lifts your concrete slab floor upwards, the sinking movement of your floor will be permanently halted.

Often, it will also be possible to lift the concrete slab back to a level position.


A foundation slab pier after installation and grout injection has been completed in a Oshawa home.

Inject Grout Fill

Once the concrete slab has been lifted, a void will be present underneath the floor.

Additionally, if your floor had been sinking because of compacted soil or washout, a gap existed even before the installation.

To address this, we carefully pump grout under the slab to fill in all empty spaces.


Repairing the cored holes in the concrete slab floor with fresh concrete and cleaning up the Burlington home.

The Cleanup

At Foundation Supportworks of Ontario, we take pride in leaving your home looking clean and neat. Once the installation is completed, we repair all cored holes with concrete, making your final installation virtually invisible.

Any debris generated during the installation is cleaned up and removed by us. And once we're done, you can rest easy, knowing that that you have a 25-year warranty on manufacturer's defects, as well as a performance warranty from us.

What NOT To Do

As with most home repairs, some work all of the time, some work some of the time, and some don't work at all. Here are three "fixes" that we at Foundation Supportworks of Ontario do NOT recommend:

Jackhammering a slab floor in a Oakville home.

A concrete slab being jackhammered and removed during a floor replacement in Whitchurch-Stouffville. A typical replacement can take several weeks to complete.

Concrete Slab Replacement:

To perform a job like this, all home furnishings, floor coverings, and interior walls must be removed. Then a crew jackhammers the existing floor into small pieces and removes them by hand.

Once this is complete, a new floor is poured and the homeowner must allow two weeks for the grout to cure sufficiently.

The interior partition may be rebuilt, floor coverings may be reinstalled, and home furnishings may be returned.

While this situation is disruptive and expensive, the real problem here is that the issue that caused the problem in the first place has not been addressed.

Without addressing the soil problems that lead to the floor cracks, your new floor may "break" over time too!

smoothing out the grout in a slab releveling project in Richmond Hill

A contractor smoothing out a surface of releveling grout during a concrete slab repair. The previous concrete floor had shown cracks during settlement.

Releveling Grout On Top Of The Slab:

To begin this process, all floor coverings that were placed on the slab must be removed. The floor is then prepared so that grout will be able to bond with the slab surface.

A self-leveling grout is poured along the slab surface, where it begins to fill in the low portion of the floor and create a level surface. After the grout is allowed to cure for several days, the floor coverings can be replaced.

However, if the floor wasn't prepared properly, the grout may not bond well to the surface of the slab, leading to chunks of it breaking off.

Additionally, the grout will add weight to the slab, potentially making the situation worse by causing further settlement.

And, just like with the last two options, the real problem of soil settlement is not addressed!

Looking For Foundation Slab Repair Contractors In ON?

At Foundation Supportworks of Ontario, we provide proven solutions for concrete slab floor leveling -- as well as other foundation repair solutions -- to homeowners throughout Ontario. We provide each of our customers with a free, no obligation slab repair quote, in writing, before any work is done. To schedule your appointment, call or e-mail us today!

Our service area includes Toronto, Mississauga, Brampton, and nearby areas such as Markham, Hamilton, Richmond Hill, Vaughan, Burlington, Oshawa, Oakville, Barrie, St. Catharines, Kingston, Whitby, Guelph, Ajax, Pickering, Clarington, Newmarket, Peterborough, Kawartha Lakes, Caledon, Aurora, Georgina.

Drying & Shrinking of the Soil Under the Slab

HVAC (Heating, Venting, and Air Conditioning) systems may be installed beneath the floor slab. Over time, the ductwork can leak air, which can dry out the soil.

As the soil dries and shrinks, gaps form under the floor slab, creating voids. Because the soil no longer supports the floor slab, the floor begins to crack and sink into the voids.

street creep symptoms in a driveway in Whitchurch-Stouffville

Washout of Soil Under the Slab

This is usually caused by plumbing leaks. If the plumbing leak is severe and there is a path for the water to flow through, it can wash soil out from under the slab.

With a void underneath the floor, there's nothing supporting the concrete slab anymore. In time, it begins to crack and sink downwards.

garage walls cracking due to street creep

Poor Compaction of Fill Soil

During construction of a new home, layers of soil are commonly moved around or spread out to get to the desired grade level. When the home is built, footings may be deepened to extend below weak fill soils and avoid a foundation settlement issue.

The slab, however, remains on the fill soils. If the fill was poorly compacted, the fill soil compresses and settles, and a void is formed under the slab. In time, the slab cracks, breaks, and settles into the void.

foundation wall cracks due to street creep in Whitchurch-Stouffville
Serving ON including the Greater Toronto area
Our Ontario Service Area
Cities in Province of Ontario
Acton
Ajax
Alberton
Algonquin Highlands
Allanburg
Allenford
Alliston
Alma
Alton
Ancaster
Angus
Annan
Ariss
Arkell
Ashburn
Aurora
Ayr
Badjeros
Bala
Baldwin
Ballinafad
Barrie
Baysville
Beamsville
Beaumaris
Beaverton
Beeton
Belfountain
Belle Ewart
Belwood
Berkeley
Bethany
Binbrook
Blackstock
Bloomingdale
Blue Mountains
Bobcaygeon
Bognor
Bolsover
Bolton
Bond Head
Borden
Bowmanville
Bracebridge
Bradford
Brampton
Branchton
Brantford
Brechin
Breslau
Brougham
Burlington
Burnt River
Caesarea
Caistor Centre
Caledon
Caledon East
Caledon Village
Caledonia
Cambray
Cambridge
Cameron
Campbellcroft
Campbellville
Campden
Canfield
Cannington
Carlisle
Cavan
Cayuga
Cedar Point
Cedar Valley
Chatsworth
Cheltenham
Christian Island
Churchill
Claremont
Clarksburg
Coboconk
Cobourg
Coldwater
Collingwood
Concord
Conestogo
Cookstown
Copetown
Courtice
Creemore
Crystal Beach
Cumberland Beach
Desboro
Dobbinton
Dundalk
Dundas
Dunnville
Dunsford
Duntroon
Eagle Lake
East Gwillimbury
East York
Eden Mills
Egbert
Elmvale
Elora
Erin
Etobicoke
Everett
Fenelon Falls
Fenwick
Feversham
Fisherville
Flesherton
Floradale
Fonthill
Fort Erie
Freelton
Georgetown
Gilford
Glen Huron
Glen Morris
Glencairn
Gooderham
Goodwood
Gormley
Grand Valley
Grassie
Gravenhurst
Greenbank
Greenwood
Grimsby
Guelph
Guelph-eramosa
Hagersville
Haliburton
Halton Hills
Hamilton
Hampton
Hannon
Hawkestone
Hawkesville
Haydon
Heathcote
Heidelberg
Hepworth
Hillsburgh
Hillsdale
Holland Centre
Holland Landing
Honey Harbour
Honeywood
Hornby
Hornings Mills
Huntsville
Inglewood
Innisfil
Irondale
Jacksons Point
Janetville
Jarvis
Jerseyville
Jordan Station
Kemble
Kendal
Keswick
Kettleby
Kilworthy
Kimberley
King City
Kinmount
Kirkfield
Kleinburg
Lake Of Bays
Laurel
Leaskdale
Lefroy
Leith
Limehouse
Lindsay
Linwood
Lions Head
Lisle
Little Britain
Locust Hill
Longford Mills
Loretto
Lowbanks
Lynden
Mactier
Manilla
Mansfield
Maple
Mar
Markdale
Markham
Maryhill
Maxwell
Midhurst
Midland
Milford Bay
Millbrook
Miller Lake
Millgrove
Milton
Minden
Minesing
Minett
Mississauga
Moffat
Moonstone
Morriston
Mount Albert
Mount Hope
Nanticoke
Nestleton Station
New Dundee
New Lowell
Newcastle
Newmarket
Newtonville
Niagara Falls
Niagara On The Lake
Nobleton
Norland
North York
Norval
Nottawa
Oakville
Oakwood
Ohsweken
Orangeville
Orillia
Oro
Oro Station
Orono
Orton
Oshawa
Palgrave
Pefferlaw
Penetanguishene
Perkinsfield
Petersburg
Phelpston
Pickering
Pontypool
Port Carling
Port Colborne
Port Dover
Port Elgin
Port Hope
Port Mcnicoll
Port Perry
Port Robinson
Port Sandfield
Port Severn
Port Sydney
Priceville
Prince Albert
Proton Station
Puslinch
Queenston
Queensville
Rama
Ravenna
Richmond Hill
Ridgeville
Ridgeway
River Drive Park
Roches Point
Rockton
Rockwood
Rosemont
Rosseau
Sandford
Sauble Beach
Scarborough
Schomberg
Seagrave
Sebright
Selkirk
Severn Bridge
Shakespeare
Shallow Lake
Shanty Bay
Sharon
Sheffield
Shelburne
Sherkston
Singhampton
Smithville
Southampton
St Agatha
St Anns
St Catharines
St Clements
St Davids
St Jacobs
Stayner
Stevensville
Stokes Bay
Stoney Creek
Stouffville
Sunderland
Sutton West
Tara
Tavistock
Terra Cotta
Thornbury
Thornhill
Thornton
Thorold
Tobermory
Toronto
Torrance
Tottenham
Townsend
Township Of Wilmot
Troy
Udora
Unionville
Utopia
Utterson
Uxbridge
Vaughan
Victoria Harbour
Vineland
Vineland Station
Virgil
Wainfleet
Wallenstein
Walters Falls
Warminster
Wasaga Beach
Washago
Waterdown
Waubaushene
Welland
Wellandport
Wellesley
West Guilford
West Montrose
Whitby
Whitevale
Wiarton
Williamsford
Willow Beach
Windermere
Woodbridge
Woodville
Wyebridge
Wyevale
York
York.
Zephyr

Cities in Whitchurch County, ON
Stouffville

Please call us at: 1-888-370-1132
bild
TCA Logo WSIB Logo