Drywall Bulges: Causes, Solutions, and Preventions

Guy conducting a wall inspection

Last Updated on May 18, 2024 by Kravelv

It is not uncommon for homeowners to come across drywall bulges, which can be quite unsightly as they create bumps or protrusions on walls that are otherwise smooth. These bulges can diminish the visual appeal of a room and potentially signal issues with the drywall installation or structural problems within the wall. Within this guide, we will explore the factors behind drywall bulges, methods for recognizing them, and the necessary measures to successfully repair and avoid them.

Key Takeaways:

  • Drywall bulges can result from various factors such as moisture exposure, poor installation techniques, structural issues, and temperature fluctuations.
  • Identifying drywall bulges involves visual inspection, running your hand over the surface, and conducting a tapping test to detect irregularities.
  • Repairing drywall bulges entails assessing the damage, cutting out the damaged area, replacing it with new drywall, sanding and finishing, and priming and painting the repaired area.
  • Preventing future drywall bulges requires proper installation, moisture control, structural maintenance, and temperature regulation measures.

What Causes Drywall Bulges?

Drywall bulges can stem from various factors, including:


Exposure to moisture can cause the drywall to swell and bulge. This moisture can come from sources such as leaks, humidity, or improper sealing.

Poor Installation

Incorrect installation techniques, such as inadequate screw or nail placement, uneven joint compound application, or improper framing, can lead to bulges over time.

Structural Issues

Structural movement or settling can exert pressure on the drywall, resulting in bulges. This may occur in older buildings or those with foundational issues.

Temperature Fluctuations

Extreme temperature changes can cause expansion and contraction of the materials behind the drywall, leading to bulges.

Poor Ventilation

Inadequate ventilation in a room can lead to the buildup of moisture, especially in areas such as bathrooms, kitchens, or basements. This excess moisture can permeate the drywall, causing it to swell and bulge over time.

Excessive Weight or Pressure

Hanging heavy objects on walls without proper support can exert undue pressure on the drywall, leading to bulges or even cracks. This is especially common in areas where shelves or cabinets are installed without sufficient reinforcement.

Impact Damage

Accidental impacts or collisions with furniture, appliances, or other objects can cause localized damage to the drywall, resulting in bulges. Even minor incidents can compromise the integrity of the wall surface and lead to visible deformations.

Termite or Pest Infestation

In regions prone to termite or pest infestations, these creatures can damage the structural components behind the drywall, such as studs or framing. As a result, the drywall may bulge or warp as the underlying support weakens.

Subpar Material Quality

The use of low-quality drywall materials or subpar construction practices can contribute to bulges. Inferior drywall may be more susceptible to warping, swelling, or delamination, particularly in areas with fluctuating environmental conditions.

Improper Humidity Regulation During Installation

During the installation process, if the humidity levels in the environment are not properly regulated, it can affect the drywall’s ability to bond effectively with joint compound and other materials. Improper humidity levels can lead to inadequate drying times, resulting in bulges as the materials settle.

Each of these additional causes highlights the diverse range of factors that can contribute to the formation of drywall bulges. By addressing these underlying issues, homeowners can take proactive steps to prevent or mitigate the occurrence of bulges in their walls.

Identifying Drywall Bulges

Accurately identifying drywall bulges is a crucial step before proceeding with any repairs. Here are detailed methods to help you pinpoint and assess drywall bulges effectively:

Visual Inspection

Begin by examining the walls under good lighting conditions. Natural light during the day or strong artificial lighting can help highlight any irregularities. Stand at various angles to the wall to notice shadows or protrusions that indicate a bulge. Look for any raised areas that break the smooth surface of the drywall.

Run Your Hand Over the Surface

Using your sense of touch can often reveal bulges that are not immediately visible. Gently run your hand over the wall, feeling for any unevenness or raised sections. Pay particular attention to areas near seams, corners, or where fixtures such as windows and doors are installed, as these spots are more prone to issues.

Tapping Test

The tapping test involves lightly tapping on the wall with your knuckles or a small tool, like the handle of a screwdriver. Listen carefully to the sound produced. A solid, consistent sound usually indicates a properly attached drywall. In contrast, a hollow or muffled sound can signal areas where the drywall has detached from the studs, indicating a potential bulge or void behind the wall.

Check for Moisture

Moisture can cause drywall to swell, leading to bulges. Use a moisture meter to check for high levels of moisture in areas showing signs of bulging. Alternatively, look for visible signs of moisture such as water stains, discoloration, or mold, which often accompany bulging caused by water damage.

Look for Structural Clues

Examine the surrounding structure for any signs of stress or movement. Cracks in the drywall, gaps between the wall and ceiling, or misaligned door and window frames can indicate underlying structural issues contributing to the bulge. Structural movement may push the drywall out of alignment, creating noticeable bulges.

Use a Level or Straightedge

For a precise assessment, place a level or straightedge against the wall. Any deviation from the flat surface will be apparent, helping you identify areas where the drywall is not flush with the framing. This tool can also help you determine the extent of the bulge and plan the necessary repairs more accurately.

Identifying drywall bulges with these methods ensures you understand the extent and cause of the problem, allowing for effective and targeted repairs.

Repairing Drywall Bulges

Once you’ve accurately identified the drywall bulges, the next step is to repair them to restore the smooth and even appearance of your walls. Follow these detailed steps to effectively repair drywall bulges:

Assess the Damage

Begin by evaluating the extent of the bulge and its underlying cause. If moisture is the issue, ensure the source of the moisture is fixed before proceeding with repairs. Check for any signs of mold, mildew, or water damage, and address these problems to prevent recurrence. If the bulge is due to structural issues, consult a professional to rectify any foundational or framing problems.

Release Pressure

If the bulge is due to moisture or temperature fluctuations, allow the wall to dry or stabilize. Use a dehumidifier in damp areas and maintain consistent indoor temperatures to avoid further expansion and contraction of the drywall. Once the wall is dry and stable, you can proceed with repairs.

Cut Out Damaged Area

Use a utility knife or drywall saw to carefully cut out the bulging section of drywall. Cut a rectangular or square shape around the bulge, making sure to cut along the center of the nearest studs for better support when attaching the new piece of drywall. Be cautious not to cut too deeply and damage any electrical wiring or plumbing behind the wall.

Prepare the Area

Clean the exposed area to remove any dust, debris, or loose material. Inspect the framing to ensure it is intact and not damaged. If necessary, reinforce the framing with additional wood supports to provide a sturdy base for the new drywall.

Replace with New Drywall

Measure and cut a new piece of drywall to fit the opening. Place the new piece into the hole and secure it to the studs using drywall screws or nails. Space the fasteners about 6-8 inches apart along the edges of the drywall. Ensure the new piece is flush with the surrounding wall surface.

Tape and Apply Joint Compound

Apply drywall tape over the seams where the new drywall meets the existing wall. Use a taping knife to smooth the tape and ensure it adheres well. Then, apply a layer of joint compound over the tape, feathering the edges to blend with the surrounding wall. Allow the compound to dry completely, usually for 24 hours.

Sand and Finish

Once the joint compound is dry, sand the area with fine-grit sandpaper to achieve a smooth, even surface. Be careful not to sand too much, as this can damage the drywall. Apply additional coats of joint compound as needed, sanding between each coat until the repaired area is seamless with the rest of the wall.

Prime and Paint

Prime the repaired area to ensure proper adhesion of the paint. Choose a primer suitable for drywall, and apply it evenly over the patched section. Once the primer is dry, paint the area to match the existing wall color and texture. You may need to apply multiple coats of paint to achieve a uniform finish.

Additional Tips for Repairing Drywall Bulges

Use Quality Materials: Invest in high-quality drywall, joint compound, and tape to ensure a durable and long-lasting repair.

Work in a Well-Ventilated Area: When sanding and applying joint compound, make sure the area is well-ventilated to avoid inhaling dust and fumes.

Feather Edges: When applying joint compound, feather the edges to create a smooth transition between the new and existing drywall. This technique helps to hide the repair and makes it less noticeable.

Patience is Key: Allow adequate drying time between coats of joint compound and paint. Rushing the process can result in an uneven or unsatisfactory finish.

Preventing Future Bulges

To prevent drywall bulges from recurring, consider the following preventive measures:

Proper Installation

Ensure drywall is installed correctly, with adequate fasteners and joint compound application.

Moisture Control

Address any sources of moisture in the home, such as leaks or high humidity levels, to prevent swelling of the drywall.

Structural Maintenance

Regularly inspect the structural integrity of the building to identify and address any issues that may affect the stability of the drywall.

Temperature Regulation

Maintain consistent temperature levels within the home to minimize expansion and contraction of materials behind the drywall.

When to Call a Professional

While many drywall bulges can be repaired with DIY methods, there are situations where calling a professional is the best course of action. Consider seeking professional help in the following scenarios:

Extensive Damage: If the bulge covers a large area or if there are multiple bulges throughout your home, a professional can provide a more efficient and thorough repair.

Structural Issues: If the bulge is due to structural problems, such as foundational issues or significant settling of the house, a professional assessment is crucial. Structural issues often require specialized knowledge and equipment to address properly.

Moisture and Mold: If the bulge is caused by water damage and you suspect mold growth, it’s essential to call a professional. Mold remediation requires specific safety protocols and expertise to ensure complete removal and to prevent health risks.

Electrical or Plumbing Concerns: If the bulge is near electrical wiring or plumbing, it’s best to hire a professional to avoid accidental damage to these systems, which could result in more significant issues or hazards.

High-Quality Finish Required: For areas where a flawless finish is critical, such as highly visible walls or specialty finishes, a professional can ensure the repaired area blends seamlessly with the rest of the wall.

How Much Does It Cost?

The cost of repairing drywall bulges can vary widely based on several factors, including the extent of the damage, the cause of the bulge, and the region in which you live. Here’s a breakdown of potential costs:

DIY Repairs

Minor bulges can often be repaired with basic supplies like joint compound, drywall tape, and sandpaper. These materials typically cost between $20 and $50, making DIY a cost-effective option for small projects.

Professional Repairs

For professional drywall repair, costs can range from $200 to $800, depending on the extent of the damage and the complexity of the repair. This estimate includes labor, materials, and finishing.

Extensive Damage or Structural Repairs

If the repair involves addressing structural issues, moisture damage, or mold remediation, costs can increase significantly. Structural repairs might range from $1,000 to $5,000 or more, depending on the severity of the problem and the required interventions.

Additional Costs

Keep in mind potential additional costs, such as repainting the wall ($200-$500), replacing insulation if it was damaged by moisture, or repairing electrical and plumbing systems if they were affected.

Tips for Hiring a Professional

Get Multiple Quotes: Obtain estimates from several contractors to ensure you get a fair price. Be wary of quotes that are significantly lower than others, as this may indicate lower-quality work.

Check References and Reviews: Ask for references and read online reviews to gauge the quality and reliability of the contractor’s work.

Verify Licensing and Insurance: Ensure the contractor is licensed and insured to protect yourself from liability and ensure they meet local building codes and standards.

Ask About Guarantees: Inquire if the contractor offers any guarantees or warranties on their work, providing you with peace of mind in case issues arise after the repair.

Drywall Bulges Frequently Asked Questions

How can I tell if a bulge in my drywall is serious?

Serious bulges may be accompanied by cracking or visible structural damage. If in doubt, consult a professional for an assessment.

Can I repair drywall bulges myself, or should I hire a professional?

 Minor bulges can often be repaired DIY, but extensive damage or underlying issues may require the expertise of a professional.

What steps can I take to prevent drywall bulges from occurring in the future?

Proper installation, moisture control, structural maintenance, and temperature regulation are key preventive measures.

Final Words

It is not uncommon to come across drywall bulges, which can have a negative impact on both the visual appeal and structural integrity of your walls. With a deep understanding of the causes, accurate identification of the issue, and adherence to proper repair techniques, you can effectively restore your walls.

Kravelv is a full time digital marketer and part time furniture and cabinet maker. During his free time he would like to create something out of recycled woods, this varies from toys, furnitures plant boxes etc. Follow him on Twitter | Pinterest | Facebook