What Is Parging and Why Calgary Homeowners Need It
Parging is a thin layer of mortar applied to the exposed area of the concrete foundation. The purpose of parging is to smooth out the uneven surface of the foundation, seal minor imperfections, and provide a protective barrier from moisture and the elements.
Freshly applied parging on a residential foundation in Calgary // Credits Google Business Profile
Simply put, parging protects the foundation of your home.
In Alberta, foundations are continually subjected to extreme conditions. The heavy rainfall of springtime causes the melting snow to saturate the soil around the foundation. Once the rain stops, the saturated soil exerts greater hydrostatic pressure on the foundation walls. Overnight, the temperatures drop, and the water that was previously trapped in the foundation walls freezes, causing it to expand. It is this expansion that causes the cracks in the foundation walls.
Modern parging products have been engineered to withstand the wide range of temperature fluctuations found in Alberta (from -40°C to +35°C) without failing to adhere to the substrate.
There is also a practical side to parging. The Alberta Building Code mandates that all below-grade walls be protected from moisture. While parging is just one of several lines of defense (weeping tiles and membranes also play a significant role), parging is a visual and effective barrier to prevent water from entering the structural concrete.
In other words, Calgary’s foundation protection starts at the surface.
5 Signs That Your Foundation Requires Parging
Damage to the foundation of your home typically occurs slowly. Below are some of the common indicators of potential damage:
1. Cracks Larger Than 2mm
Fine cracks are typical and acceptable during the curing process of concrete and as the foundation walls settle. However, once a fine crack grows larger than approximately 2mm, it presents an opening for water to enter the structure. Given the harsh environment of Calgary’s climate, a single freeze-thaw cycle can cause even the smallest of cracks to expand rapidly.
2. Efflorescence (White Powdered Substances)
Efflorescence is the appearance of a chalky white substance on the surface of your foundation. This occurs when water migrates through the concrete and deposits minerals on the surface. When left untreated, this process will continue indefinitely: water enters the foundation, minerals exit the foundation, and the surface of the foundation deteriorates.
3. Pieces of Parging Are Peeling Away
If chunks of parging are peeling away, cracking, or separating, then the protective coating has failed. Without a protective coating, the exposed concrete is now vulnerable to precipitation (rain, snow, etc.). This is generally when parging repair in Calgary is required.
Once the protective coating is damaged or dislodged, patch jobs to repair the area rarely last longer than a few years unless the surface is properly prepared prior to application.
4. Moisture Appears in the Walls Following a Chinook Event
Chinook events are unique to this region. During Chinook events, the temperature can fluctuate by 30 degrees Celsius or more in a very short period. Should you find moisture on the walls of your basement during or immediately following a Chinook event, this is likely the result of the rapid thawing of ice that caused water to infiltrate the weakened parging.
Multiple cycles of this type of moisture penetration will further accelerate the damage to your home’s foundation resulting from freeze-thaw.
5. There Is a Musty Smell in the Basement
Occasionally, the warning signs are not visible on the exterior of your home. A persistent musty smell emanating from the vicinity of your exterior walls could be indicative of a slight amount of moisture entering the basement. Although there may be no apparent source of moisture leaking into your basement, the deterioration of the parging can still create enough moisture to contribute to elevated levels of humidity inside your home.
At this point, the maintenance of your home’s surface has transitioned to becoming a concern regarding the interior of your home.
Consequences of Ignoring Foundation Issues in Alberta
Minor foundation problems tend not to resolve on their own.
It usually starts with a hairline crack. Water enters through the crack during periods of heavy rain or snowmelt. The water then freezes overnight and expands, creating additional stress to the foundation wall. Repeat this process multiple times throughout the year (Alberta receives more than 100 freeze-thaw cycles annually), and the damage to the foundation compound rapidly accelerates.
Eventually, minor surface deterioration can reveal the structural concrete of the foundation. Increased moisture intrusion will occur, reduced performance of insulating materials will occur, and in extreme situations, drywall or flooring can become impacted due to increased moisture.
Additionally, there are resale implications for homeowners. Visible evidence of deterioration of the foundation in Calgary’s highly competitive real estate market can potentially reduce the value of your home by $3000 to $5000. Buyers note the condition of the exterior of your home, and inspectors always comment on it.
Preventative parging in Calgary is far less expensive than repairing the structural components of your foundation.
How to Get Parging Done: What to Expect
While many individuals who live in Calgary may have never had parging completed, the parging process is relatively straightforward when carried out by experienced professionals.
Inspection
The contractor reviews the foundation for cracks, indications of moisture issues, and areas where the parging has separated from the foundation. Not all cracks are structurally significant, therefore distinguishing between them is important.
Preparing the Surface
This is the critical step of the process. Any loose debris is removed, the surface is thoroughly cleaned, and any unstable sections of the foundation are chipped down to solid concrete. Failing to prepare the surface properly will lead to premature failure of the parging.
Sealing Cracks
Prior to applying new parging, any cracks are properly repaired and sealed. Depending on the extent of the damage, this may require specialized patching compounds or repair mortars.
Applying the New Parging
A fresh layer of mortar is evenly applied to the exposed section of the foundation wall. High-quality parging products specifically designed for use in Alberta’s extreme temperature fluctuations are utilized to ensure maximum flexibility and durability.
Finishing and Curing
The surface is finished or textured to blend with the aesthetic of your home. The final curing phase is crucial; failure to cure the parging properly can compromise adhesion.
Generally speaking, the entire process can be completed in one to three days, depending on the size of your home and the weather conditions. Provided the parging is applied properly, the new parging can last up to 20 years with little to no maintenance.
Do-It-Yourself vs. Professional Parging
Home improvement centers sell parging products. Tutorials online appear to make it easy. Yes, some cosmetic repairs can be made by a handy homeowner.
However, Calgary’s climate does not tolerate mistakes.
Correct adhesion to the substrate is dependent upon careful preparation. The parging product mix ratio must be optimized for the temperature and humidity of the area. The application of the parging product must be uniform. If the bond is broken, you will be back to square one within a couple of years.
Local masons certified by the Red Seal Association understand how soil conditions, drainage patterns, and freeze-thaw cycles impact foundations. In addition, many reputable firms provide warranties on their workmanship, something DIY projects rarely offer.
When comparing parging costs in Calgary, short-term savings should be weighed against long-term durability.
Protecting Your Foundation Prior to the Next Freezing Temperature Drop
Repairing the foundation of your home is extremely expensive. Preventive maintenance is not.
A timely parging project for your Calgary home will enhance the strength of your home’s first line of defense against moisture, stabilize minor cracks before they widen, and maintain the clean and tidy appearance of the exterior of your home.
For homeowners in Calgary, Okotoks, Airdrie, Chestermere, Cochrane, Banff, or Canmore, the optimal time to arrange for an assessment is either in the early spring or late summer. By waiting for visible damage to develop, you limit your options.
If you have observed cracks, flaking, or moisture signs, we recommend scheduling a consultation with a reputable local stonemason contractor (such as Martini Stone Masonry) to determine whether you require minor parging repair services in Calgary or a full foundation replacement.
To learn more about the costs associated with parging in Calgary, please refer to our detailed parging cost guide. Alternatively, you may request a complimentary assessment via our contact/free quote page.
A small repair today will prevent a more extensive repair tomorrow.