How Winter Affects Your Basement Foundation

How winter affects your basement foundation

Winter can be a very dangerous time for your basement foundation. Dry, cold, and wet weather can all cause damage to it, especially the combination of cold and wet weather. Don’t let your basement foundation become a disaster. A reliable foundation professional can help you remediate damage and prevent the risk of further damage in the future.

We’ve compiled information about all the leading causes of basement foundation damage in winter. We also explain how to recognize signs of damage and when you need help from a contractor.

Hydrostatic Pressure

The weight of water accumulated in the soil around your foundation causes hydrostatic pressure, which makes water seep through the pores in your concrete wall. This pressure pushes inward on the walls, shifting and damaging them and driving more water through the concrete. Common effects of hydrostatic pressure are bowing and wall cracks.

Does the wall seem to be “leaning” inward? Do you see horizontal, step-shaped, or diagonal cracks? Hydrostatic pressure could be the reason.

Homeowners should inspect their basements for cracks that have widened or new cracks that have formed at regular intervals. Other signs of overwhelming pressure include cracks with one side slightly pushed in or ones that appear to be bulging. This can happen if the foundation wall is bowed.

Dry Weather

Dry weather can be just as bad as wet weather in winter. Due to loss of moisture, the soil contracts, creating a void as it pulls away from your basement foundation. Then, the foundation starts to settle. It’s important to catch foundation settlement early on because damage becomes more expensive to deal with as time goes on. It’s possible to use a foundation repair system where your house’s weight is transferred to more suitable and stable soil mechanically.

Freezing and Thawing

Freeze-thaw cycles inflict damage on foundations as well as asphalt and concrete driveways. The concrete foundation wall absorbs water, which then freezes and expands. The expansion leads the concrete to crack under the pressure. Subsequent cycles exacerbate this damage.

Water fills the cracks and freezes, widening them and weakening the foundation’s integrity. You may be thinking this will reverse itself as temperatures go back up. Actually, it gets even worse. The ice has widened the small cracks and as it melts, the water starts flowing into your basement freely.

Frost Heave

With time, your basement foundation may begin to shift because of frost heave. This happens when the moisture in the soil around the house freezes and swells. It puts additional pressure on the foundation. The added pressure from lateral soil can cause large cracks. Masonry caulk can be used to seal cracks that are less than a quarter of an inch wide.

Come spring, your basement may get flooded because of oversaturation of the soil around the foundation.

Heavy Snow

Heavy snow piling up near your basement foundation can lead to flooding. Gaps where the soil was compressed are filled. When the snow melts, it puts pressure on the basement walls, cracking them and letting water flow into the basement.


Apart from melting snow, two common causes of erosion in the yard are sleet and rain. This will affect the basement foundation. Water flowing down from the eaves can result in erosion, exposing the foundation’s base.

In order to direct water away, your yard’s grade should slope away from the foundation. This slope can be altered by erosion.

One situation where erosion is very likely is if your home’s gutters are misplaced or twisted and miss most of the water that cascades down from the roof. You can reckon with quite a few issues if you have gutter sections missing or if the gutters overflow because they’re not big enough or sloped to a sufficient extent. This makes it impossible for them to eliminate the rain your roof collects.

If your downspout spews water as soon as it reaches the ground near the building, you can expect erosion around the basement foundation. Downspouts should carry the water at least five feet out into the yard. If this isn’t the case with yours, we recommend adding downspout extensions.

Recognizing Signs of Damage

Common signs of foundation damage or settlement include leaning or bowed basement walls, uneven or sloping garage or basement floors, interior drywall or plaster wall cracks, cracks in foundation walls, and chimney leans or tilts. Leaning or bowing finished interior or brick exterior walls indicate damage too. Other signs are cracks in the mortar and alignment issues or gaps in doors and windows. Be wary of frequent leaks; they might signal foundation sinking.

What You Can Do

Sump pumps are installed to transport water away from the house. Your pump might have become faulty. It’s a good idea to have battery backup for the pump, especially in winter, when power outages are more frequent. Your sump pump can make the difference between a flooded and a safe and dry basement. You must ensure free, unobstructed flow of water away from your home.

If sump pump water collects and freezes, the pump will stop functioning or even sustain permanent damage.

Make sure your discharge line has been placed properly and hasn’t frozen. It should be resting on a downward slope, preventing water from staying inside and freezing.

Clean your gutters regularly. Water should be able to flow freely through rather than over them, going right into the basement foundation. Your foundation will be compromised by any water pooling. Water will leak into the basement with nowhere else to go. If the process goes unheeded, the water will penetrate the walls and cause mold, mildew, and other damage that’s going to be much harder and costlier to remedy.

In winter, always shovel or blow snow away from the foundation. It should never be allowed to rest next to your home. Piles of snow are a water torrent waiting to attack your house.

Quick Action is Needed

If damage to your basement foundation has emerged, don’t believe it will go away on its own. The problems will continue, inflicting further damage to your property. This damage will reduce its value and cost you a pretty penny in repairs.

If you suspect your basement foundation has been compromised, contact Foundations First. We repair foundations in the areas of Hamilton, Peel, Halton, Haldimand, Brantford, Paris, Binbrook, Guelph, Cambridge, Kitchener, and Waterloo. Contact us by phone or email or use our appointment request form to book an appointment.


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