Because mild temperatures tend to dominate Texas during the winter, potential freezing and thawing aren’t typically considered a great threat to our Houston homes. But cold weather can still be very detrimental to your home. That’s because low temperatures along with occasional snowfall, freezing rain, and ice can irreversibly affect your foundation and cause extensive structural damage throughout your home. To understand how the February snow storm and cold outbreak might have impacted your foundation, let’s take a look at some of the adverse effects that freezing temperatures and snowfall can have on a house foundation.
Cracks Caused by Frost Heave
Although frost heave rarely happens in Texas, repeated freeze-thaw cycles could cause this condition to occur in any area characterized by mild winters. When the temperature drops below 32°F after a snowfall or freezing rain, the soil freezes on top, turning the present moisture and water into ice. As soon as the weather warms up, the melting snow and ice will start to saturate deeper soil layers. If the cold weather returns, the water trapped in the soil will refreeze and expand, causing the soil to expand as well. The longer the cold weather sticks around, the more it permeates the soil. As a result, underlying soil layers freeze and expand at deeper depths, even below your foundation. Because this expansion can create a great deal of pressure underneath your home, it could lead to an upheaval movement, which may cause cracks to develop in your foundation, slab, walls, floors, and ceilings.
Cracks due to the Thermal Expansion and Contraction of Concrete
Extremely cold weather is known to cause significant temperature fluctuations within a concrete foundation. Typically, the exterior perimeter of a foundation cools and freezes rapidly, while the middle area underneath the home remains warmer. Because the cooler section of the foundation contracts more than the warmer section, tensile stresses often develop between the frozen and warmer areas of concrete. When these stresses are high enough, they result in cracking. Besides leading to new cracks, repeated expansion and contraction of your concrete foundation could cause existing cracks to grow larger and deeper.
Foundation Shifting due to Freeze-Thaw Cycles
Contrary to popular belief, clay soil can crack due to fluctuations in the soil water content during any season. Just like the drought conditions that occur during the summer, dry spells during the winter can remove a lot of moisture from the soil, causing it to crack, shrink, and pull away from your foundation. This could lead to cracks and voids underneath your foundation and around the perimeter of your home. If snow accumulates near your home during the cold weather, your foundation and the soil surrounding it could soak up a lot of water once the snow and ice start to melt. Because melting snow and ice typically saturate the soil at deeper depths than a gentle summer rain, the soil may become very soft. This reduces its ability to support the load of your home. But clay soil also tends to absorb water at different rates. An area of the soil that absorbs more water can become soft faster, causing one corner or side of your foundation to sink more readily than the rest. As a result, your foundation will start to settle in an uneven fashion. This process is commonly referred to as differential settlement.
Drainage Issues Caused by Erosion
Soil erosion often occurs when snowmelt or rainwater runs along the ground surface after the soil becomes saturated. Because soil erosion can alter your landscape slope, which may prevent water runoff from being effectively diverted away from your foundation, it could lead to foundation damage. Additionally, the water coming from overflowing gutters or downspouts that have been directed incorrectly can erode the soil near your foundation, exposing its base. As a result, your foundation may absorb a lot of water, which could also lead to different foundation issues down the road. To prevent drainage problems and reduce the risk of foundation damage due to snowmelt and rainwater, you need to regrade your landscape when required so that it always slopes away from your home, clean your gutters at least 2 times a year, and redirect downspouts as needed.
Cold weather can cause unwanted damage to a Houston home, whether it’s older or recently built. To prevent foundation problems due to cold weather, it’s important to prepare your Houston home for winter each year and inspect its exterior on a regular basis and after every weather event that could have negatively impacted it. But even more important than this is to have known foundation issues fixed by experienced professionals as soon as possible. That’s because harsh conditions, such as cold weather, periods of heavy rain, and drought, can only lead to the problem getting worse, eventually increasing the repair costs!