Foundation Heave

Experts in Foundation and Slab Repair in Greater Ottawa & Nearby Areas of ON 

diagram of foundation slab that is experiencing upheaval

Foundation upheaval can lift an entire structure, but more often it forces parts of a foundation or slab upwards, while other sections remain stationary.

Either way, the damage that results will require the expertise of a foundation repair specialist

The problem:

Your foundation or slab floor is moving upwards, leading to cracks in the walls and floors of your home.

Telltale signs:

  • Cracking on inside walls (common)
  • Cracking on outside walls (rare)
  • Cracks on the concrete floor slab
  • Displaced or tilting slab sections
  • Cracks joining together to form a triangle

How we can fix it:

Unwanted water accumulating in the soil under your home – and the pressure it brings -- is typically the cause of slab and foundation heave. The Foundation Guys Inc.’s first priority will be to eliminate water sources wherever possible. We will check for underground water line leaks, clogged drains, broken sprinkler lines, as well as faulty gutter and leader systems. Once we have fixed water problems, we can begin making repairs like:

  • Concrete grinding for minor heaves, especially in outdoor slabs
  • Soil stabilization by polymer injection to resist water infiltration
  • Mechanical foundation repair, that can both support your foundation and to keep it from heaving in the future

Other causes for heaving include tree roots and pressure from adjacent buildings. Regardless of the cause, an authorized foundation contractor is the best person to evaluate foundation heaving problems and suggest suitable solutions for your home.

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We solve foundation heave problems! Call us for a free slab or foundation upheaval repair quote today!

We serve Kanata, Orleans, Ottawa, Nepean, Gloucester, and many nearby areas in Ontario.

What Causes Foundation Upheaval?

Heave is the upward movement of a foundation or slab caused by underlying soils that expand or swell. This occurs due to an increase in moisture or by freezing forces. Heave is more common with slabs than foundations because slabs have less weight to resist heaving forces. Unless there is a long period of drought, heave most commonly occurs within the first few years of the building's construction.

Slab and foundation heave is most commonly caused by these four forces:

samples of wet and dry clay

Expansive Soils

A house built on soils with high clay content will be susceptible to heaving forces because clay-rich soil expands significantly when it gets wet.

The excavation for a foundation often gives the soil around and under a house a chance to dry out and shrink, as shown in the photo at right. After the house is built, clay-rich soil that gets soaked during wet spells can cause heaving problems, while also damaging foundation walls.


Frost on a grassy hill with a frost-covered tree.

Frost Heave

Water increases in volume by nearly 10% when it freezes, and wet soil can expand even more when frozen. When wet soil freezes the resulting pressure can cause the slab or foundation wall to shift and crack.

The colder the temperature, the deeper the soil will freeze. Frost forces can lift a foundation dramatically - sometimes by several inches - leading to serious heave damage.


Diagram of a broken pipe underneath a foundation slab.

Plumbing Leaks

Leaks or breaks in plumbing lines that run underneath a concrete slab or through a foundation wall can deposit moisture underneath the foundation and slab. This moisture can be from supply lines, waste lines, or even your home's HVAC system.

Over time, this moisture can cause the soils underneath the foundation to expand, which will then cause them to push up on the structure above.


Heavy rains in a downpour in Williamsburg.

Prolonged Or Heavy Precipitation

Too much precipitation combined with too little drainage away from the house will lead to increased moisture underneath your foundation. Moisture that comes into contact with expansive soil can result in heaving of your foundation and slabs.

Precipitation can also cause expansion in the soils on the sides of your foundation, leading to bowing, buckling walls.

What NOT To Do:

cracks in a slab floor consistent with slab heave in Prescott.

Cracks on floor slabs that are caused by foundation heave are unique in their appearance.

You will see multiple cracks that come together to a point or form an enclosed loop where the heave is greatest.

Before doing any repairs to your foundation, it's important to identify the problem as heaving.

Some contractors who have not been fully educated on the signs of heave can easily misread the cracks in your home and suggest the wrong solution.

The problem? While heave is the opposite of foundation settlement, the symptoms are often similar. To an untrained eye, it may appear that the exterior walls are going down — when what's really happening is that the basement slab is being pushed up near the center of the house.

To apply the right solution to a foundation problem, make sure you're getting the right diagnosis.

More about sinking concrete slab floors.

Repairing Heave Damage

Start by having an experienced foundation repair specialist inspect your foundation issue and identify what is causing your problem. Once the problem is identified, a customized solution can be proposed to repair the damage and address the cause of the issue.

We Do Foundation Heave Repair in ON!

At The Foundation Guys Inc., we have the tools and training available to fix foundations and slabs that are experiencing problems with upheaval.

We offer foundation and slab heave repair quotes to all within our Ontario service area. If you would like to schedule a free, no-obligation appointment with one of our foundation specialists, call or e-mail us today!

We proudly serve Gloucester, Ottawa, Kanata, Orleans, Nepean, surrounding areas such as Richmond, Smiths Falls, Carleton Place, Vanier, Renfrew, and nearby.

Looking for a price? Get a no cost, no obligation free estimate.

our service area

We serve the following areas

  • Almonte
  • Arnprior
  • Ashton
  • Bourget
  • Braeside
  • Carleton Place
  • Carlsbad Springs
  • Carp
  • Casselman
  • Clarence Creek
  • Clayton
  • Crysler
  • Cumberland
  • Dunrobin
  • Edwards
  • Embrun
  • Fitzroy Harbour
  • Gloucester
  • Greely
  • Kanata
  • Kars
  • Kenmore
  • Kinburn
  • Limoges
  • Manotick
  • Mcnab/braeside
  • Metcalfe
  • Morewood
  • Munster
  • Navan
  • Nepean
  • North Gower
  • Orleans
  • Osgoode
  • Ottawa
  • Pakenham
  • Ramsayville
  • Richmond
  • Rockcliffe
  • Russell
  • Saint-pascal-baylon
  • Sarsfield
  • St Albert
  • Stittsville
  • Vanier
  • Vars
  • Vernon
  • Wendover
  • White Lake
  • Woodlawn
Our Locations:

The Foundation Guys Inc.
184 Forward Ave
Ottawa, ON K1Y 1L2
1-613-702-9139
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