Although cracks in your walls can be scary, not all of them are a sign of structural damage. Some cracks in walls are harmless and are easy to fix, while others can be a sign of a more serious issue and require repairs. When should you worry about cracks in your walls? Here are some types of cracks, their causes, and what to look for to tell the difference between one that is harmless and when you should contact a professional:

6 Main Types of Cracks in Walls

Depending on what’s going on, the cause of the crack, and where it is, cracks in walls tend to fall into a few types. These are the most common types of cracks in walls you could see in a home:

1. Diagonal cracks
2. Hairline cracks
3. Horizontal cracks
4. Spiderweb cracks
5. Stairstep cracks
6. Vertical cracks

1. Diagonal Cracks

Diagonal cracks usually appear around window or door frames at a 30 to 70-degree angle. They are usually at a 45-degree angle compared to the vertical wall plane. They can be caused by poor installation, uneven settling, or moisture issues in the soil under the home. If you see diagonal wall cracks, it’s worth having a professional evaluate your home, determine the specific cause, and make sure things are repaired before they cause bigger issues for your home.

Poor installation damages your home, and not just in things like windows and doors. If the soil under the home was not compacted evenly during construction, it can lead to uneven settling. If there is a drainage issue, it can cause moisture to accumulate under the house, which causes the soil under the house to expand differently and at a different rate than the soil around the perimeter of the home. This can also lead to uneven settling, which may cause diagonal cracks in the walls around windows and doors.

2. Hairline Cracks

Hairline cracks are the most common type of wall crack. They also tend to be harmless and are the least concerning of the types of wall cracks you might come across. Hairline cracks are generally about a millimeter wide; these are the thin, skinny cracks that usually appear in drywall. Generally, hairline cracks are superficial and repaired with easy cosmetic fixes.

3. Horizontal Cracks

Horizontal wall cracks are a cause for concern and a sign that you should call a professional for an evaluation. When you see a horizontal crack in drywall, it’s usually a sign of a larger issue. They can be caused by a foundation that is settling unevenly, a water drainage issue, or both.

4. Spiderweb Cracks

Spiderweb cracks have multiple small fissures that extend out in all directions, which makes them look like a spiderweb. Small spiderweb cracks are usually a small drywall problem, while larger cracks can be a sign of a structural issue.

Usually, the thin, tiny spiderweb cracks are caused when drywall finishing materials are too thick. As they dry, they fracture into the spiderweb-like cracks. In this case, the cracks are hairline and usually thinner than 1/16-inch. Repairing it requires removing the old compound layer and applying a thinner new layer that won’t fracture when drying.

Larger cracks or cracks that are getting bigger can be a sign of structural issues. In this case, you’ll want to contact a professional to inspect your home, identify the source, and recommend next steps.

5. Stairstep Cracks

A stairstep crack is a type of wall crack that combines vertical and horizontal cracks in a stepped pattern. When they occur, they tend to be on the exterior of a home near openings for a window and door and follow the pattern of masonry.

Stairstep cracks are caused by the home settling or issues with the masonry, like an issue during the bricklaying. Brick ties are the connection to the house framing. If these are missing, poorly done, or failing, it will cause weak spots in the brick facade, which can lead to cracks over time.

In the case of bricks, those with failing or weak ties will feel loose if you try to move them. Repairing these is a matter of removing the affected bricks and reinstalling the brick ties. However, if you are seeing stairstep cracks and cannot move the bricks, it could be a sign of a foundation issue.

6. Vertical Cracks

Vertical cracks in walls are usually not concerning, but some of them can be a sign of a structural issue.

Vertical Cracks That Are Not Concerning

A vertical crack on a non-load-bearing wall that is also very straight is usually not a cause for concern. More than likely, this is a crack that is appearing along the seam where two drywall sheets are coming together. Typically, it’s caused by imperfections in the drywall taping, which is repairable.

Vertical Cracks That Are a Concern

Some vertical cracks are concerning. You could be dealing with a structural issue if you see a vertical wall crack that is:

• On a load-bearing wall
• Larger than ¼-inch wide
• Expanding (in length and/or width)
• Multiplying (e.g., many vertical cracks)

Vertical cracks showing these characteristics are potential signs of structural damage or an issue with your home’s foundation. In this case, it’s best to have a professional take a look and examine your home to determine what’s going on and what may need to be repaired.

What Can Cause Cracks in Walls?

Wall cracks can be caused by several different things, including:

1. Construction or installation mistakes
2. New homes settling
3. Homes shifting over time
4. Moisture issues or leaks
5. Temperature changes and fluctuations
6. Structural problems

1. Construction or Installation Mistakes

Mistakes during construction or during the installation of windows, doors, stairs, etc. can also cause cracks in walls. A common construction mistake that can lead to wall cracks is when the taping over drywall panel seams does not have enough joint compound to keep it stuck firmly to the wall. This can create a weak spot where the tape starts to pull away from the wall over the seam, which is often the cause of fine, thin vertical cracks.

2. New Homes Settling

Newly built homes or new home additions on existing homes often have small wall cracks that show up over time. These are common and are considered house-settling cracks. Usually, it’s recommended to wait about a year after new construction or new builds before repairing cracks to let materials have time to settle.

After the first year, you can make cosmetic repairs on any cracks without having to worry about more appearing as new materials continue to settle. However, if you see cracks reappearing in the same area or cracks that are getting wider, it’s a good idea to have an inspection done.

These could be signs of uneven settling or a water drainage issue. If there is a water drainage issue, it could be a reason to consider a retaining wall, depending on your lot and soil. Retaining walls can help prevent soil erosion, manage drainage and water runoff, and more.

3. Homes Shifting Over Time

New builds will settle, but homes of any age will shift subtly over time. Cracks tend to appear in the weakest area of a wall as these shifts occur over time. This is why hairline cracks are the most common types of wall cracks and why they tend to appear around doors and windows. If you see other wall cracks that are concerning, then you know it’s time to bring in a professional.

4. Moisture Issues or Leaks

Moisture issues and leaks can wreak havoc on your home over time. Leaks around windows, roofs, attics, and more can cause water to get into a wall’s framing and the drywall, causing it to deteriorate and soften. Not only does this damage your home, but it can also lead to mildew, mold, and other issues.

In these cases, wall cracks will often also have yellow or brown staining from the water. If the leak is recent, it might also feel damp when you touch it. Before repairing the crack, it’s important to locate and fix the source of the leak to keep it from recurring and to prevent further water damage to your home. This is one of the things homeowners should not delay fixing.

5. Temperature Changes and Fluctuations

Changing temperature and humidity levels can create a cycle of expansion and contraction in framing members and drywall. Over time, this can result in wall cracks. A lack of climate control in a home to help control temperature swings can result in more cracks.

This is why vacation homes or homes that are unoccupied for a few months at a time can be prone to cracks in walls and ceilings. It’s also one of the reasons why drafty doors or windows, poor insulation, improper ventilation, and more can contribute to problems in your home.

6. Structural Problems

Structural problems will usually cause cracks to form. Structural problems that can cause wall cracks include:

• Shifting foundations
• Sinking foundations
• Termite damage to supporting wood members
• And more

Wall cracks caused by structural issues are silent signs your house has problems. Structural issues like these will often result in diagonal cracks and jagged cracks, like stairstep cracks. If you see these types of wall cracks or cracks wider than ¼ inch, there is a potential issue with your home’s structure, and you’ll want to bring in a professional to do a structural inspection. They will be able to:

• Evaluate your home’s structure
• Identify the issue and the source of the issue
• Provide some guidance and next steps for repair

When Should You Worry About Cracks in Your Walls?

Some wall cracks can be harmless, while others are signs of structural damage you should not ignore. You should contact a professional about cracks in your walls if you see:

• Diagonal cracks
• Stairstep cracks
• Horizontal cracks
• Multiple cracks in one area
• Cracks in load-bearing walls
• A crack that is wider than ¼ inch
• Cracks that are expanding or getting bigger
• Cracks that reappear in the same area
• Cracks and signs of water damage
• Cracks in an area on both the inside and outside the home
• Cracks that appear after a big storm or natural disaster

Categorize Wall Cracks to Help Determine When to Call a Professional

When figuring out the difference, it can be helpful to categorize cracks as:

• Cosmetic
• Serviceable
• Structural

Cosmetic cracks are usually not a concern, while serviceable cracks and structural cracks are more concerning and require a professional.

Cosmetic Wall Cracks

Cosmetic cracks are harmless cracks, like hairline cracks, that are superficial and easy to repair and are usually fine to DIY, if you want to.

Serviceable Wall Cracks

Serviceable cracks are more noticeable and tend to affect the building exterior or envelope. They are repairable. Although they are not necessarily an emergency, it’s still important to contact a professional to evaluate the issue and make necessary repairs.

Structural Wall Cracks

Structural cracks are often signs of more serious issues and should be handled as soon as possible. The issue may not always require a foundation repair, but structural cracks are signs of bigger issues. It’s important to contact a professional you trust and have your home evaluated to figure out what’s going on and what needs to be fixed.

Update and Maintain Your Home With Zephyr Thomas

Not all wall cracks are a problem, but it does depend on the type of crack, where it is occurring, what it looks like, and whether it’s changing. If you have any concerns about cracks in your walls, it’s a good idea to reach out to a contractor you trust to take a look. They’ll be able to help you determine whether a wall crack is harmless and normal, requires some minor repairs, or is a sign of structural damage that might require bigger repairs.

Whether you are starting a new home improvement project or are taking care of some maintenance and repairs for your home, Zephyr Thomas can help! Give us a call at 717-399-4708 to schedule your free estimate. We also offer handyman services to help you cross maintenance tasks off your to-do list.