5 Causes of Basement Floor Cracks

Here are 5 reasons why basement floor cracks

Basement floor cracks are one of the most common problems faced by many homeowners. Cracks can vary in size, but if it’s wider than one-eighth of an inch, then it should be a cause of concern. We are going to explore the 5 main causes of basement floor cracks below.

Concrete Shrinkage

  • Most of the basement floors are made up of concrete as it is economical, sets quickly, and is considered to be highly durable. Concrete is basically a mixture of cement and water. Once it is poured, it is left to dry and harden. While it is drying, it also shrinks to some extent. If the temperature drops too much while the concrete is drying, it will affect the rate of shrinkage and cause cracks. If the temperature increases, it will dry rapidly and thus cracks will start to appear.

Cracks appearing on concrete basement floors are considered to be a natural phenomenon. Experts state that it is almost impossible to avoid these cracks. An experienced professional will try to mitigate the risk of cracking by limiting the cracks to specific areas. Cracks will most likely be visible near doors and sharp corners. Although these cracks will hardly affect the structural integrity of your home, they cause other problems such as water seepage and pests. If these cracks are not fixed early on, they will worsen over time.


  • Settlement is another natural phenomenon that occurs when the soil beneath a newly built house moves and shifts around. This is when the soil is loose and adjusts due to the weight of the house. The same phenomenon occurs when the concrete is drying up. The soil under the concrete floor shifts, and thus causes cracks to appear. Most engineers and architects allow for about 1 inch of soil movement so that structural and foundation damages can be avoided. There are some warning signs which you as a homeowner must lookout for. These include gap formation in floors, walls, ceilings, and walls pulling away from each other.

If you notice any of these warning signs, it means that the settlement has caused a lot more damage to your home than just basement floor cracks. You must immediately hire a professional to fix these problems before the situation worsens.

Structural Problems

  • If the newly built house has weak foundations or improper basic structure, it will cause cracks to appear not only on the concrete floor but also on the walls and the ceilings.

If the house is newly built, and cracks appear within the first few months, then it is a serious problem that should be dealt with without any delay.

Frost Heave

  • basement floor cracksFrost heave is most similar to settlement but it occurs only during the winter season. When the temperature drops to extremely low levels, the ground freezes and then thaws the next day. This freezing and thawing lead to the ground shifting, especially where it is experiencing a lot of load such as underneath your home.

This shifting of the ground leads to cracks in the basement floor, especially near pillars, support columns, and corners. There are several ways to minimize the risk of basement floor cracks due to frost heaving.

Inadequate Waterproofing

  • Before starting a basement flooring and finishing project, it is imperative that the basement be adequately waterproofed. This involves several measures such as installing windows for fresh air ventilation, a humidistat fan to keep moisture low, a sump pump to manage ground seepage, and installing drains that lead water away from the basement and the house.

Inadequate waterproofing measures allow water to seep into the basement through the floor. This causes cracks to appear which may worsen over time and cause structural problems for the house. Repairing this damage is going to cost a lot of money.

If you are a homeowner that is worried about basement floor cracks, then give us a call at 877-727-2259. We at Crack-X are a civil structures repair company operating in Maine and New Hampshire. We will inspect your property and take the necessary measures to prevent your basement floor from cracking.

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