{"id":2955,"date":"2022-11-24T20:21:55","date_gmt":"2022-11-24T15:21:55","guid":{"rendered":"https:\/\/marcoreparationdefondation.com\/the-effects-of-winter-on-your-foundation\/"},"modified":"2026-10-07T23:33:20","modified_gmt":"2026-10-07T18:33:20","slug":"the-effects-of-winter-on-your-foundation","status":"publish","type":"post","link":"https:\/\/marcoreparationdefondation.com\/en\/the-effects-of-winter-on-your-foundation\/","title":{"rendered":"Frost Heave and Your Foundation: The Effects of Winter"},"content":{"rendered":"

Winter acts on a foundation through frost: water in frost-susceptible soil freezes, forms layers of ice that push the soil upward, and the thaw that follows weakens that same soil.<\/strong> The damage is rarely dramatic. It usually shows up as a new crack, a door that sticks in spring or water at the wall during the melt, which is why checking your foundation after winter matters as much as preparing it before.<\/p>\n

The explanations below come from two digests of the National Research Council of Canada, CBD-182, Frost Action and Foundations<\/a> (K.N. Burn, 1976) and CBD-128, Adfreezing and Frost Heaving of Foundations<\/a> (E. Penner and K.N. Burn, 1970), plus the APCHQ Performance Guide<\/a> (edition consulted: 2006, in French) and CAA-Qu\u00e9bec. The NRC digests are older, but they describe the physics of frost, which has not changed.<\/p>\n

What Causes Frost Heave?<\/h2>\n

Three conditions must be met together, according to the NRC: the soil must be frost-susceptible, water must be available in sufficient quantity, and cooling conditions must freeze the soil and the water. In this process, water moves from unfrozen soil toward the freezing zone and collects in layers of ice, called ice lenses, that force soil particles apart and raise the surface.<\/p>\n

Not every soil does this. Clays, silts and very fine sands support the growth of ice lenses, while coarse-grained soils such as sand and gravel do not heave. That is one more reason the clay described in our article Soil Type and Your Foundation<\/a> matters in Quebec.<\/p>\n

How Does Frost Push on a Foundation?<\/h2>\n

Two ways. First, if the soil freezes down to the footing, nothing resists the heave: the NRC says the soil must not freeze down to the top of the footing. Second, through adfreezing, when frozen soil bonds to the wall surface and transmits its upward movement through that bond. The NRC notes that adfreezing becomes destructive only in frost-susceptible soils, and that placing footings below the frost line does not necessarily ensure protection in such soils.<\/p>\n

The APCHQ sets the matching standard for new builds: footings and foundation walls must be protected from frost so as to eliminate any risk of damage. Its listed corrections include raising the ground level or insulating the outside of the foundation and the footings properly.<\/p>\n

The NRC’s digest on adfreezing deals mainly with unheated structures, such as attached garages and carports, basement garages and cottages. If your house has one of these, it is the part to watch first.<\/p>\n

What Happens When the Ground Thaws?<\/h2>\n

The NRC notes that rapid thawing causes soil to lose shear strength, which can destabilize foundations and supports. Spring also brings meltwater to the wall. CAA-Qu\u00e9bec advises checking that downspouts discharge 2 m away from the foundation, and our articles on gutter systems<\/a> and the 4 kinds of water damage that threaten a foundation<\/a> explain why water at the wall is the problem to solve first.<\/p>\n

Which Signs Show Winter Damage?<\/h2>\n