What to do if you notice cracks on the walls in your home

What may be the causes, how to tell if they are enlarging, and when to worry

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By Kenny G

cracks on the walls

Special cracks on the walls at home: an unfortunate event that often happens and that a reader recently asked us about:

Can someone help me and tell me why cracks appear on the walls at home and what can I do? Thank you in advance for your help, Maria.

Let’s try to understand together how to address this problem.

Cracks on the walls at home: possible causes

Let’s start by reassuring you: if your house is new, it is normal for cracks to occur as a result of the settling of the walls.

  • If the house is not new, we need to understand the reasons for the settling, specifically:
  • If it’s a single crack,
  • If there are multiple cracks,
  • How deep and long they are,
  • Where they are located,
  • If any demolitions or excavations have been recently carried out near your house,
  • If there have been landslides nearby,
  • If heavy rains have caused soil erosion,
  • And in extreme cases, if there have been floods or earthquakes.

The important thing to understand is whether the cracks are superficial and harmless or if they indicate structural damage.

Cracks are a result of movement in the ground. If they are due to soil movement, it could be a phenomenon that has already occurred and the cracks are just a visible consequence.

Crack on the exterior wall, concerning, branching out and forming an “X” shape, vertical to the potentially nearby load-bearing pillar.

However, if there has been significant ground movement caused, for example, by heavy rainfall and earthquakes, it is possible that the settling is still ongoing and this movement can cause more serious damage.

Cracks in the ceiling

It is also possible for folds to appear in the gypsum board ceiling. In this case, it depends on when the ceiling was installed. Are the cracks small? Are there many of them? How deep are they? Are they only in the ceiling or do they also affect the masonry? When did they appear?

One of the most probable causes in this case is that the structure to which the panels are attached has undergone expansion due to high temperatures, causing the gypsum boards to crack.

If the cracks are deep, you need to determine if there are any leaks, if there have been impacts on the panels, or if the work was poorly done. If the cracks appear shortly after the completion of the work, it means that it was not done properly.

It is best to immediately contact the person who carried out the work, as they are responsible. Most likely, the panel was not properly reinforced, and the joints need to be done properly to prevent cracks.

Conclusion: What to do in case of cracks on the walls at home

If the cracks are “dangerous” based on what we explained earlier for a non-recently constructed house, and if you live in a condominium, it is best to immediately inform the administrator and request that an engineer be called for an inspection.

If you live in a standalone house, we recommend doing the same and doing it as soon as possible. It is better to have an additional assessment rather than suffer more significant consequences in the future.

A technician or a structural engineer who visits the site in person can tell you what is happening, whether it is due to ground movement, if the structure is leaning in one direction or another, or if the ground beneath the structure is giving way, just by looking at the cracks.

cracks on the walls

As previously mentioned, cracks that are deep, branching out, and forming an “X” shape are the most alarming. They could be simple and minor superficial cracks, but it is always wise and reassuring to have a professional assessment.

Q&A: Other Questions

Now let’s address some additional questions on the topic that you asked later.

What is a crack meter, and what is it used for?

If the cracks are not normal and settlement causes concern, how can they be monitored?

There are tools available on the market called crack meters that can help. They are essentially millimeter-scale strips that are placed on the crack to record movement.

These are plates made of friable material, such as plaster, which are applied to the wall like a band-aid covering the two sides of the crack.

If the sides move apart, the plate fractures, and the crack becomes visible on the plate.

Some people also use a thin glass with lime, which achieves the same result.

Others are made of plastic and indicate movement in millimeters. Typically, engineers use the ones that fracture for their reports. Plastic ones are only used to monitor time/movement.

How to use them:

Start with the most significant cracks, as they can widen even slightly within a few months.

If the plate fractures, you can see when and how much movement has occurred.

Before calling and paying for a structural engineer, you can buy one, two, or three crack monitors and install them on the cracks, monitoring them for a certain period, at least six months.

If movement occurs within two weeks, be cautious and immediately contact a structural engineer in an urgent manner.

What to do in case of cracks in the floor

Here the issue is very delicate, and here’s the question:

Good morning, I live on the second floor of a house and I noticed cracks in the marble floor. I want to immediately tell you that my neighbor who lives on the first floor and also owns the cellar below her apartment, about 5 years ago, excavated to lower the height of her cellar… could there be a connection?

The answer is very delicate, it’s better to immediately call a technician. Something serious may have happened: by excavating her cellar, the structure may have given way and suffered damage. It wouldn’t be the first time, but the neighbor is responsible for paying for the damages:

Did she ask for permission for the excavation? She doesn’t own the subsurface, so you should have given consent for this work because it’s a common asset.

You can request the restoration of the floor and the original height, as well as compensation for the damages caused.

All about walls at home

Lots of advice on the walls of your home.